After Alicia went home with her mother, the group gathered to discuss their plans for the next two nights of the sleepover. They unanimously decided to head to the arcade.

“Do you guys want to go to the arcade?” Tommy asked.

“I’m on board with that,” Mason replied.

Excitedly, the group made their way to the arcade, only to find it closed for maintenance.

“What now?” Mason inquired.

“We could head to the mall,” suggested Mackenzie. “It’s almost lunchtime, and we should think about grabbing a bite to eat.”

“I’m in favor of that plan. Lunch sounds great right now,” Mason agreed.

“I’ll catch up with you all shortly. I need to take this call,” Olivia announced as she stepped aside. “Hi Dad, what’s up?”

“Can’t you find a sitter? I’m out with friends right now,” Olivia complained.

“Fine,” she said, sounding exasperated.

“Everything okay, Olivia?” Mason asked with concern.

“My dad needs to go somewhere and wants me to watch Abby. He’ll meet us at the mall. I hope that’s alright with you guys,” Olivia explained.

“Yeah, that’s fine,” Mackenzie reassured her.

With that, the group headed to the mall.

“Where did your dad say he would meet us?” Mason asked.

“He said he’d meet us by the food court. Look, there he is!” Olivia said, spotting her father as he approached with Abby, who clearly was not pleased to be there.

“Hey, Dad,” she greeted him.

“Hi Abby.”

“Hey there, sweetheart. I apologize for the last-minute change,” Olivia's dad said.

“It’s fine,” Olivia replied. “Will you pick her up when you’re done, or should I take her home?”

“I can come pick her up. I should be finished by 4:00. Be good, Abby, and listen to your sister. Thanks again, Olivia, for helping me out. Love you both. Bye,” said their father.

“Bye, Dad. Love you too,” Olivia responded, watching him leave with a sigh.

“Alright, everyone, we have the entire day ahead of us to do as we please,” said Mackenzie. “Is everyone okay with splitting up?” 

“That works for me,” responded Mason. “Tommy and I are thinking of checking out the comic book store, if that’s alright.” 

“That sounds good,” replied Mackenzie. “Who would like to join me at the magic shop?” 

“I will!” exclaimed Justin. 

“Great! Olivia, I assume you plan to spend the day with your sister,” said Mackenzie. 

“Yep, and knowing her, I’ll end up doing everything she wants while I get to do none of what I’d like,” Olivia replied. 

“I can hear you, you know,” Abby interjected, and the group dispersed to pursue their individual interests. 

“Let’s reconvene here around 5:00,” Mackenzie suggested. “Max and Monica, what are your plans?” 

“I think I’ll check out the toy store,” said Monica. 

“I’m heading to the music store,” Max added. 

“Alright, sounds good,” Mackenzie replied, and the group went their separate ways to enjoy their day. 

An hour later, Mason and Tommy were still browsing the comic book store when Olivia burst in, looking frantic. 

“Olivia, what’s wrong?” he asked, sensing her distress. 

“It’s Abby. I can’t find her anywhere, and Dad’s going to kill me!” Olivia exclaimed. 

“Olivia, take a deep breath and tell me what happened,” Mason urged. 

“We were at the ice cream shop getting treats because she wanted some. Then she asked to go into the pet store, but I told her Dad wouldn’t let us get another pet, and we got into a huge argument. She ran off after that,” Olivia explained, her voice shaky. 

“It’s alright, Olivia. We’ll find your sister,” Mason assured her. “Let’s find Mackenzie first, and then we’ll start our search for Abby. Tommy, would you like to join us, or would you rather stay here?” 

“Let’s go,” Tommy replied, and the three of them set off to find Mackenzie, who should still be at the magic shop.

"Mackenzie, there you are!" Mason exclaimed. "I've been searching everywhere for you." 

"Mason, what's wrong?" Mackenzie inquired. 

"Olivia's sister is missing," Mason replied. 

"What?! How did that happen?" Mackenzie gasped, as Olivia began to recount the story of how she lost her sister at the mall. 

"I think our first stop should be the pet store, since Abby mentioned she wanted to go there," Mackenzie suggested, leading the group toward the shop. 

Upon arriving, they approached the front desk. "Excuse me, sir, have you seen this girl?" Mackenzie asked. 

"Yes, she was here just a few minutes ago. I believe she went to check out the reptiles," the clerk responded. 

"Do you know where she went afterward?" Mackenzie pressed. 

"All I know is that she was looking at the reptiles, then she asked about a price and left," the clerk explained. 

"Wait, you said she asked for a price. Was she interested in something specific?" Mackenzie questioned. 

"I think she mentioned wanting a turtle," the clerk replied. 

"Turtles are her favorite animals; she's always wanted one!" Olivia added. 

"Thank you for the information," Mackenzie said. Turning to Olivia, she asked, "Does Abby have any other favorite stores in the mall?" 

"Let’s see... she loves the candy store, the toy store, the ice cream shop, the arcade, and the bookstore," Olivia listed. 

"If she was looking to buy a pet turtle, the bookstore would be the perfect place for her to read up on them," Mackenzie reasoned. "I think we should head there next." 

The group made their way to the bookstore in search of Abby. Upon arrival, they approached the front desk once more. "Excuse me, have you seen this girl?" Mackenzie asked the clerk. 

"Yes, she was here not long ago," the clerk replied. "Do you know if she was searching for anything specific?" Mackenzie asked.

“I believe she mentioned she was searching for the animal section,” said the clerk. “Did she purchase anything?” Mackenzie inquired. “She asked about the price of a specific book, but I don’t think she actually bought it,” replied the clerk. “Was it a book about turtles?” Mackenzie asked. “How did you know that?” the clerk replied, surprised. “Just a hunch,” Mackenzie said with a smile. 

“I think I’m starting to understand what Abby might be up to, but we should check the other stores to be sure,” Mackenzie continued. “Let’s head to the toy store next.” The group made their way to the toy store, where they approached the staff member on duty. 

“Excuse me, sir, have you seen this girl?” Mackenzie asked. “Yes, she was here,” the clerk responded. “Was she looking for anything specific?” Mackenzie probed. “Perhaps something related to turtles?” 

“Yes, I told her we had stuffed turtles, but she wasn’t interested. I asked if she was looking for something specific, and she simply inquired about the direction to the animal toys. After that, she returned with one of those grow-a-turtle toys and asked how much it was. Then she just left,” explained the clerk.

“Let me recap this,” Mackenzie began. “First, she goes to the pet store and wants to buy a turtle, but realizes it’s not within her budget. Next, she visits the bookstore to learn about raising a turtle but discovers it’s too much work. Then, she decides the next best option is a toy that grows when submerged in water.”

“Let’s go to the game store next,” Mackenzie suggested, and the group made their way there. “If she couldn’t have a real turtle and a toy turtle, maybe she thought a digital version would suffice,” Mackenzie speculated.

They arrived at the game store and began to ask the clerk a few questions.

“Excuse me, have you seen this girl?” Mackenzie inquired.

“Actually, yes. She was here just a few minutes ago. She mentioned that she was looking for a game about raising animals,” the clerk replied.

“A turtle, perhaps?” Mackenzie guessed.

“Yes, that’s precisely what she asked for,” the clerk confirmed.

“Did she ask about the price of the game?” Mackenzie continued.

“Yes, she did, but then she left,” the clerk said.

“So, she’s going from store to store, inquiring about turtle-related items, asking for prices, and then just walking away?” Mason asked. “Why is that? Does she expect these items to be free, or does she not have enough money to buy anything?”

“Those are valid questions,” Mackenzie acknowledged. “But I think we should move on to the next store.”

Mason looked at his sister, puzzled. “The next store is the candy shop. I don’t think they’ll have anything related to turtles,” he said.

“You’re right. It seems she’s only visiting places that sell turtle-related items. Olivia, does Abby enjoy going to the art store?” Mackenzie asked.

“Actually, yes! I forgot to mention that,” Olivia replied.

“I think I know where she is,” Mackenzie said, and the group made their way to the art store, where they found Abby sitting at one of the art tables, engrossed in a project.

“There you are! Abby!” Olivia exclaimed. “Please don’t ever run off like that again. I was worried sick about you. I know you really want a turtle, so maybe I can convince Dad to get one for you as a Christmas present, though I can’t make any promises.”

“Really?!” Abby said, her eyes lighting up. “Thanks, Olivia, and I’m sorry I ran off.”

“That’s okay. Do you want to show me what you're working on?” Olivia asked.

“A turtle sculpture! I want you to have it,” Abby offered.

“That’s probably the nicest thing you’ve ever done for me,” Olivia replied, smiling.

"I'm sorry too," Olivia said. "I shouldn't have raised my voice like that. You won't tell Dad that I ran off, will you?" Abby asked anxiously. 

“I promise I won’t mention that you ran off if you agree not to tell him that I yelled at you. It will be our little secret, okay?” Olivia replied.

“Oh, by the way, it’s almost time for him to pick you up. Let’s head back to the food court. I need to meet my dad, who should be coming for you soon,” said Olivia.

“Sounds good! We’ll meet you there shortly,” Mackenzie said. 

As they made their way back, the group returned to the food court where Olivia’s dad was waiting to pick up Abby.

“Hi, Dad,” Olivia greeted him.

“Hey, kids! I hope Abby wasn’t too much trouble,” their father replied.

“No trouble at all,” Olivia assured him. “Dad, I know you said no more pets after we got the dog, but could you make an exception for Abby? She really wants a turtle.”

“I’ll think about it,” their dad responded, oblivious to the fact that he had secretly already bought Abby a turtle as a surprise Christmas gift.

“Have fun at the rest of your sleepover, honey, and thank you for taking care of Abby,” Olivia’s dad said as he and Abby headed home.

“Is everyone ready to head back?” Mackenzie asked. Once everyone was accounted for, they all agreed and set off for the twins’ house, where they would enjoy two more nights of sleepover fun until Mason and Mackenzie’s parents returned from their getaway.

Eventually, the weekend came to an end, and it was time for everyone to go home. The twins spent a significant portion of the day tidying up the house in preparation for their parents' return.

“Looks like they’re back,” Mason announced as he noticed their parents arriving. 

“Hey kids, how was your sleepover? I trust it was trouble-free,” their father inquired.

“No trouble at all,” Mackenzie replied.

“Speak for yourself,” Mason muttered under his breath.

“What do you mean by that?” Mackenzie asked, raising an eyebrow.

“Nothing,” Mason dismissed. “Anyway, how was your trip?”

“It was very relaxing,” their mother said with a smile. 

“What do you say we go out for dinner?” their dad suggested eagerly. “I’m starving!”

“Sounds great to me,” Mason agreed. “I could use a break from all the mystery-solving we’ve been doing these past few months.”

"You know it's never that simple," Mackenzie remarked. 

"I know," Mason replied, as the family headed out to dinner after a long weekend spent unraveling mysteries for the twins.