A week had passed since the Barnes family returned home after a hotel stay following a break-in. The twins were happily playing in their new treehouse when Melissa reminded them that Mackenzie had a doctor's appointment soon to check on her leg. 

"Mackenzie, I just wanted to remind you about your doctor's appointment for your leg," Melissa said. 

"Okay, Mom," Mackenzie replied. 

"I haven't spoken to Olivia since we got back, so I should probably give her a call," Mason added. "I hope she isn't too upset with me." 

"I'm sure she’ll understand once you explain everything that happened while we were away," Mackenzie reassured him. 

"Yeah, you're right," Mason acknowledged. As the two climbed down to get in the car for Mackenzie’s doctor appointment 

Upon their arrival, the family walked into the lobby and approached the front desk. "Hello, we have an appointment for Mackenzie Barnes," Melissa informed the receptionist. "Of course!" the receptionist responded with a warm smile. "Please take a seat over there; the doctor will be with you shortly." 

While they waited, Mason noticed the vending machine and wandered over to grab a snack. Just then, he heard someone call out to him. "Hi, Mason!" He turned to find Olivia standing nearby. "Hey, Olivia! What brings you here?" Mason asked. 

"My sister, Abby, broke her arm," Olivia replied. 

"What? How did that happen?" Mason asked, his concern clearly visible. 

"We're still trying to figure that out; we think it might have happened on the playground," Olivia explained. 

"Not the Barnes playground?" Mason asked, surprised. 

"No, it's a different playground she likes to visit," Olivia said. 

“Even Abby doesn’t know how it happened?” Mason asked, shifting into full detective mode. 

“She claims she doesn’t, but I can’t shake my skepticism,” Olivia replied. 

“Do you know if anyone else was with her when this occurred?” Mason inquired. 

“She was at a birthday party with friends; that’s all I know,” Olivia said.

“So, either someone did this to her and she’s refusing to reveal who, or she caused this herself and is attempting to disguise it as an accident,” Mason reasoned. 

“Would you mind if I spoke with Abby?” he asked. 

“Of course,” Olivia replied. “Perhaps you’ll have more success in uncovering the truth than we have.”

“But first, I need to check in with my mom and sister. They’re probably wondering where I am,” Mason said as he walked back over to where his mother and sister were seated. 

“Hey, Mom, guess who I ran into?” Mason said with a smile.

"Hello, Olivia. What brings you here?" Melissa asked.

"My sister broke her arm, and we're trying to understand how it happened," Olivia replied.

"I’m so sorry to hear that," Melissa said with compassion.

"Mason was just about to accompany me to her room to ask her a few questions," Olivia continued.

"I’ll be in room 103 if you need me," Mason interjected.

"Please don't take too long, dear," Melissa instructed gently.

"I won’t, Mom," Mason replied, as he followed Olivia to the room where Abby was being treated.

"Hi, Abby," Mason greeted her. "I just wanted to talk to you about what happened."

“Abby, did someone do this to you?” Mason asked, concern evident on his face. 

“I’ve already told my dad and my sister that I don’t remember anything,” Abby replied. 

“Are you absolutely sure you can’t recall what happened?” Mason probed gently. “It would help if we could talk to the kids who were at the party,” he continued. “It’s hard for me to believe she doesn’t remember anything.” 

“Yeah, maybe one of those kids saw something,” Olivia chimed in. 

Mason nodded in agreement. “We need to find everyone who was at that party,” he suggested. “Abby, do you remember whose party you were attending at the time of the incident?” 

“It was for my friend Amber,” Abby responded. 

Before Mason could ask further questions, his mom entered the room to inform him that they were heading to Mackenzie’s appointment. "Hey honey, I just wanted to let you know that the doctor is ready for us," Melissa said. 

“Okay, Mom, I’ll be right there,” Mason replied.

"Alright, Mom, I’ll be there shortly," Mason said in response. He then turned to Olivia and whispered, "We can delve into this more thoroughly later." Olivia nodded slightly, her eyes brimming with determination. Mason added, "Stay alert; we’ll uncover the truth together." A wave of relief washed over Abby, knowing that Mason and Olivia were on her side. As Mason left to join his mother, Olivia quickly grabbed a notebook. She wrote the name "Amber" in bold letters and circled it with her pen. "Let’s start with Amber," she murmured to herself as she flipped through the pages. "I’ll cross-reference everyone else who attended that party." 

Meanwhile, Mason was in the doctor's office with his mother and sister as they underwent various tests. Eventually, the doctor entered to provide an update. "Everything appears to be progressing well, and your leg is healing nicely. If this continues, you should be able to have your cast removed in about two weeks," the doctor stated. "That's fantastic news, Doctor," Melissa responded. "Now that we’re finished here, how about treating ourselves to some ice cream?" she suggested. 

“That sounds wonderful,” Mackenzie replied. “Mom, if you don’t mind, I think I’ll stay behind to help Olivia,” Mason said. “That’s perfectly fine, dear,” Melissa replied. “You two have fun—I’ll be home as soon as I’m finished here,” Mason said, waving goodbye to his mother and sister.

"I'm back," Mason announced. "Were you able to gather any new information while I was away?" 

"I found out the names of the other guests at the party," Olivia replied. "I think we should start with Amber." 

"Given that it was her party, that seems like a logical first step. However, let’s visit the playground where the incident occurred first," Mason suggested. 

"Abby, we're heading to the playground to try to piece together what happened," Olivia explained. "But before we go, I need you to think back to what you were doing when you broke your arm." 

"I think I remember being on the swings," Abby said. "I was trying to swing as high as I could, and then suddenly, I was flying through the air. After I hit the ground, everything went blank." 

"And you have no idea who might have pushed you off the swings?" Mason inquired. 

"No, I don't," Abby replied. "I’m starting to wonder if perhaps whoever did this wanted her out of the party, so they caused the injury to get her removed," Mason suggested.

"I think that's a plausible theory," Olivia said thoughtfully. "Abby, is there anyone you can think of who might not have wanted you at the party? Perhaps someone you don't get along with who could have hoped for your absence?"

"Not that I can recall," Abby replied.

"I believe we've gathered all the information we can from Abby. Let’s head to the playground," Mason suggested. Just as they were about to leave, they unexpectedly encountered one of Abby's friends from the party.

"Hi, I'm looking for Abby. Do you know which room she's in? My name is Nicholas," he said.

"Abby mentioned that you were at Amber's birthday party today," Olivia responded. "Perhaps you can help us—we're trying to figure out how Abby's arm got broken. Do you happen to know anything about it?"

"Actually, I did see Abby arguing with someone at the party just before the incident occurred," Nicholas said. 

"Do you remember who it was and what the argument was about?" Mason inquired.

“She was embroiled in a heated argument with a boy named Lucas Ambros. While I’m not entirely sure of the details of their dispute — I didn’t catch everything — I do know that Lucas has a massive crush on Abby, to the point of obsession,” Nicholas explained. 

Mason chimed in, turning to Olivia, “If Lucas had a crush on Abby, it’s possible he tried to confess his feelings to her.”

Olivia added, “But when Abby turned him down, he retaliated by pushing her off the swings.”

“Thanks for the information, Nicholas. Abby is in room 103,” Mason noted. Armed with this knowledge, they decided to speak with Amber, who was known to be Abby’s closest friend. Amber might have additional insights into what occurred between Lucas and Abby. 

“Can I help you?” Amber asked as she opened the door. 

“Hi Amber, we’d like to talk to you about Abby. We know she attended your party today, and we’re trying to understand how she ended up with a broken arm,” Olivia said.

“Come in; I’ll share what I know,” Amber replied. 

“Thank you,” Olivia responded as she and Mason stepped inside.

“Do you want to talk about Abby?” Amber asked. “We’ve heard she might have had an encounter with a boy named Lucas at your party,” Olivia remarked. 

“That peculiar kid?” Amber replied. “Let’s just say he has some serious boundary issues; he genuinely doesn’t know when to back off.” 

“We’ve been told that Lucas is obsessed with Abby,” Olivia continued. 

“Obsessed is an understatement. Lucas follows Abby everywhere and even leaves love notes in her locker,” Amber said. “His fixation on her is concerning.” 

“Maybe Abby finally confronted Lucas and told him to stop following her,” Mason suggested. 

“But Lucas couldn’t handle the rejection and retaliated by pushing her off the swings,” Olivia explained. “Amber, do you know where we can find Lucas?” 

“Just a moment while I look up his address,” Amber replied. “Here it is. Please do us all a favor and teach that creep a lesson,” Amber urged. 

“Thanks, Amber. Don’t worry; we will. By the time I’m done with him, Lucas won’t dare go anywhere near Abby again,” Olivia assured her. 

They eventually made their way to Lucas’s house.

As Olivia knocked on the door, she clenched her fists, mentally preparing herself for the confrontation that awaited her. “Olivia, I understand that you’re upset, but please try to stay calm,” Mason urged softly. After a brief pause, Lucas opened the door. 

“Hello, Lucas. May we come in for a moment? We need to discuss Abby with you,” Mason said. Lucas nodded and stepped aside, inviting them in. 

“You don’t seem surprised to see us,” Mason remarked. 

“I had a feeling this would happen sooner or later,” Lucas replied. “What did my brother do this time?” he asked.

“Wait, your brother?!” Olivia exclaimed, unable to hide her disbelief. 

“Yes, I’m Nicholas,” he introduced himself. “Lucas is my twin brother.” 

Mason and Olivia exchanged incredulous glances. 

“So the person we saw at the hospital was Lucas, not you,” Mason said, piecing it together. “Nicholas, would you mind coming with us? We need to get back to the hospital IMMEDIATELY!” 

Olivia insisted, and together, the three of them rushed back to the hospital. 

“Do you want to tell me what’s going on?” Nicholas asked, trying to catch up. 

“To keep a long story short, we believe Abby got into an argument with your brother over his obsession with her, and he retaliated by pushing her off the swings, which resulted in her arm being broken,” Olivia explained.

Upon returning to the hospital, Olivia and Mason made their way to Abby's room, where Lucas was still waiting. "Lucas, could you please step outside? We need to have a conversation," Olivia requested. "About what?" Lucas responded, feigning ignorance. "Don't play coy—we know you pushed Abby off the swings," Olivia stated firmly. "It's time to be honest." 

"Alright, fine. It’s true—I had a crush on Abby, and I wouldn’t leave her alone. During the party, she tried to tell me that she wasn’t interested in me in the same way I was interested in her, but I didn’t want to accept it," Lucas confessed. 

"So, you pushed her off the swings?" Mason inquired. 

"I did push her off the swings because I was angry. I feel terrible about it; I never meant for anyone to get hurt. I came here to apologize to Abby," Lucas explained. 

“Why did you tell us your name was Nicholas?” Mason asked. “You could have saved us a lot of trouble by just being honest.” 

"I know, and I'm truly sorry for that," Lucas replied.

"Ultimately, the most important thing is that you recognized your mistake and took responsibility for it. It was incredibly brave of you to return and apologize to her," Olivia said. Nicholas then interjected, "Lucas, how many times have I told you to stop impersonating me? It only leads to confusion!" 

"What’s he doing here?" Lucas asked.

"That’s not relevant," Nicholas replied. "What matters is that I doubt Mom and Dad will be pleased to learn that not only have you been pretending to be me again, but that you've also hurt someone." 

"Nicholas, wait! Please don’t tell Mom and Dad! I’ll do anything," Lucas pleaded as he chased his brother all the way home.

“Thank you, Mason, for helping me with this situation,” Olivia said.

“No problem! It was fun teaming up with you to solve a mystery,” Mason replied. 

“By the way, Lucas isn’t the only one who needs to apologize. I know I promised to call you as soon as I got back, but I ended up getting distracted by a series of break-ins that occurred in the neighborhood while we were away.” 

“Mason, it’s perfectly alright; you don’t need to apologize,” Olivia replied. “I understand how you become when it comes to solving mysteries—it's just part of dating a detective.” She continued, “How about we go to lunch once Abby is discharged from the hospital? Deal?” 

Mason smiled, “I can live with that.” 

“I should probably head home; it’s getting late,” he added. 

“Alright, I need to have a conversation with my sister anyway. Goodbye, Mason, and thank you once again,” Olivia said as they shared a kiss before Mason made his way home. Olivia then went to speak with her sister about everything that had transpired. "Hey, Abby, I wanted to check in and see how you're holding up," Olivia said. 

"I'm managing, given the circumstances," Abby replied. 

"I just wanted to reassure you that I don't think Lucas will bother you anymore; I'm confident he's learned his lesson," Olivia continued.

"What I don’t understand is why you didn’t come to me or Dad sooner about this. We could have addressed it earlier," Abby said.

"I know, and I’m sorry," Abby responded. "I thought I could handle it on my own."

“Thank you, Olivia, for believing in me and always being there for me,” Abby expressed with heartfelt gratitude. “That’s what sisters are for,” Olivia replied, her smile radiating warmth. They shared a tender moment before their dad arrived with Alexa to take Olivia home, giving Abby a chance to enjoy some quality time alone. 

“Hey, Dad,” Olivia greeted him cheerfully. 

“Hello, sweetheart. It’s time to head home. I’ll stay here with Abby,” Mr. Sampson responded. 

“Are you sure you don’t want me to stay with someone? I’m certain Mason and Mackenzie wouldn’t mind,” Olivia proposed. 

“No, I'm confident you’re old enough to spend the night at home by yourself now,” Mr. Sampson assured her. 

“Alright, is Alexa staying here with you, or is she coming home with me?” Olivia inquired. 

“Alexa, what would you like to do? Would you prefer to stay with me or go home with Olivia?” Mr. Sampson asked. 

“I want to stay with you,” replied Alexa eagerly.

“Hold on tight, sweetheart; I’ll be back in a moment. I just need to drop your sister off,” Mr. Sampson said. “Okay, Daddy,” Abby replied as Olivia left with their father.

Meanwhile, at the Barnes residence, Mason had just returned home after a long day at the hospital. “Hi, dear! Were you able to sort everything out at the hospital?” Melissa inquired. “We figured out what caused Abby’s arm injury,” Mason responded. “It was actually quite enjoyable teaming up with Olivia to solve the mystery,” he added with a smile. “Just don’t let your sister catch wind of that,” Melissa teased playfully. “Anyway, it’s been a long day, and I’m exhausted. Goodnight, Mom,” Mason said before heading upstairs to bed after yet another demanding day filled with challenges and mysteries resolved.

Meanwhile, Mr. Sampson had just returned to the hospital with Alexa after dropping off Olivia. Abby was already asleep, and now that the mystery of her broken arm had been unraveled, Mr. Sampson felt he could finally catch some rest as well.