This is my take on what would happen if Parker moved on after the last episode of the first season and didn't come back. I don't own any of the characters as much as I wish I did. I apologise if this is bad but I just had an idea that wouldn't leave me until I had written it.
When the team split up it hurt Parker more than she could ever admit. As much as she hated to acknowledge it, these people had become not just her team but her family in the short time they had been together and it felt like it was physically hurting her to leave them behind. After years of shutting away emotions and separating herself from others that could affect her like these people had, this sudden emotional pain came as a surprise and Parker did not like it one bit. In those months of separation she vowed she wold never see them again, it would hurt too much to get close to them again, all the while knowing it was inevitable for her to be left by them again and her fragile state couldn't take it from these people she trusted so implicitly again.
She had gone back to her thieving ways but it just wasn't the same after the work she had done with the team and all she could think about was that she had an experience of being the good guy or girl in her case and now she wanted to carry on with it so she started up her own business of helping people but with a few changes. This time she travelled where she wanted to go and looked for people to help while stealing the occasional object to sell to get money when she needed it. She made sure it was kept quiet though, she couldn't have her old team coming after her, she couldn't take the pain of seeing them again, and she most definitely couldn't have people saying that the infamous thief had gone soft, so she worked quietly helping buildings improve security by breaking in and showing them the flaws in their security systems. She often got paid for those jobs for saving the companies possibly millions and embarrassment. It worked well for her, she got the thrill of thievery but was still helping people which staved off her boredom and she got paid for it. Some of her jobs were very similar to the work that the team used to do and those hit a little close to home for Parker although she couldn't leave some of these people without the help they so desperately needed.
The defining moment for Parker came on her return to Serbia for the first time since the case with the team with the orphans. She had dropped in on Luca and his family, the Mortons, a few times, if just to satisfy her need to see that he was truly ok and wouldn't face the same upbringing that she had from that point on, but Luca and his new family were very welcoming and even made Parker feel part of their family, a real family, and it was after one Sunday lunch at their house when she decided it was time to face her fears and return to Serbia to see how the other orphans were. She had avoided Serbia and a few of the surrounding countries not wanting to come across any more situations that played with her emotions as that case had but she knew she had to go back at some point. Serbia was much like how she had left it and there were many jobs she could pull here but she was here for one reason in particular and so and soon as she landed, Parker headed straight to the orphanage that she knew most of the orphans that she rescued along with the team had been sent to. Armed with books and sweets from Luca and the Mortons and her Serbian phrase book, Parker took a deep breath and pushed open the doors. Whilst it was much better than the old warehouse they had been in before, Parker couldn't help but give an involuntary shiver as the place brought back bad memories of both her past and the job. The children surprising remembered her when she found them and she was pleased to find out that some had been adopted, although the majority were still there. They had also been taught some English making communication much easier than her botched attempts at Serbian and she had a wonderful day playing games and helping them to learn more English. The staff were so impressed with her effect on the normally relatively quiet children that they invited her back so she left with the promise to return the next day and bring their favourite treat with her, Hagen-Daaz!
Parker spent a month in Serbia working with the orphans, and maybe teaching them a little bit of lock picking, safe breaking and moving around silently - she just couldn't help it, but she had to leave after that but she left the promise to write to them and come back and visit as soon as she could. That happened to be the defining moment for Parker as she realised she was good with the children and that ultimately she enjoyed working with them as she felt she was doing good and so she incorporated visits to the local orphanages into her jobs as much as she could.
Parker had settled into a pattern when she got the invitation which threw her completely. She had been carrying on with her previous jobs improving securities, helping those in need and helping orphans come out of their shells. In fact she had a few additions to her posy. Whilst in Serbia once again, she had stumbled across some orphans being mistreated and forced to work in dangerous conditions and couldn't leave them behind. As it turned out they happened to be fluent in English and all of them had watched their families be killed and them be taken to be used in forced and unpaid labour. Parker had planned to break them out and drop them off at the orphanage that the others were at but there had been a small problem and she had ended up stuck in their warehouse with the orphans for days when a locked door had posed a greater problem than she thought it would. In this time she had bonded very closely with three of the orphans, two little girls and one little boy - Jovana or Jo as she became known, Milinka or Millie as she became known and Stevan or Steve as he became known, and once she had safely broken them all out and dropped the other orphans off at the orphanage, she had new identities made for them under several names and got paperwork made under all of her and their identities to make her their legal guardian. She used their nicknames to pass them off as Americans like her and they became her little protégés.
Parker taught them everything she knew holing them up in a warehouse in America and going through training for weeks but making sure it was as fun as she could make it and that she rewarded them with ice cream. In the time they were training, Parker made them all up rigs and once they were up to a good enough level she took them on one of her jobs with her. After a few missed attempts and close calls they learnt their lessons and within a year they were up to one of the best standards in the world. They had fitted into her pattern perfectly and enjoyed travelling the world with Parker and being home schooled as they told the Morton's when she took them to visit. Despite them all being about six, no one could be sure of their ages as they didn't know themselves, and being a couple of years younger than Luca at that point, the four of them got along so well and that left Parker to talk with the Morton.
Talk was exactly what she did when she visited not long after receiving the letter. It had come via a fellow thief who had got it from another thief who had been given it by a grifter and so on. The Morton's were the people who Parker had talked to about the hurt she had felt when the team split up and whilst they didn't fully understand, they had some insight after learning about Parker's past and so supported her decision to go alone as long as she kept in contact with them and made sure to stay safe. The letter had been an invitation but what threw Parker was the source. It was from Sophie inviting her to come and watch her play, the Sound of Music. Parker had heard a few rumours but had shied away from any information about her former team and had actively tried to avoid the possibility of being in the same place as former teammates by avoiding the areas in the rumours so this was something she automatically went to throw away. Just before she could do so she was assaulted with memories of their jobs together and how hurt Sophie would be if she didn't show up. Her main problem was she knew she would get attached if she saw them again and that could only lead to hurt as they were bound to reform the team only to have to split up again. Anyway she had her own team of sorts now and she couldn't and wouldn't just abandon Jo, Millie and Steve now after all they had been through and done together. Mrs Morton or Dana as she told Parker to call her encouraged Parker to go saying that it would give her closure and that she could slip away unnoticed if she needed to. Her husband, Joe he insisted, asked Parker if she wanted them to come but Parker had made up her mind, she was going to go with Jo, Millie and Steve but she wasn't going to be seen.
Parker and her little group of protégés or her little family as she thought of them trooped to the theatre that Sophie was performing in and made a camp in a nearby campsite. The kids loved camping and as it was close to the theatre and was unlikely to run the risk of bumping into any of her old team, Parker indulged their wished and they camped out overnight until the dress rehearsal the night before was over. The little team treated it like a mission sneaked in to scope out the place. After the discovery of some rafters where they couldn't be seen by anyone but they still had a good view of the stage they secured the area and went back to their campsite to prepare. The day of the show Parker was very nervous and her kids could tell. They loved Parker, she was their big sister they never had, and so they decided to cheer her up. The day was spent playing games in the nearby woods and practicing with their rigging in the trees which helped to relax Parker. Come the evening the four of them dressed in black and after Parker grabbed a prewritten note, the scrambled off to get in place before the show started. Parker thought there couldn't be anything worse than Sophie's acting on stage and had warned the kids but she was wrong, Sophie's singing was worse, much worse and there were a few muffled giggles from the rafters from the kids as Parker pulled faces at the sound and the kids took pictures on her phone. As the show finished Parker dropped the note off with one of the staff and the four of them clambered onto the roof of a building opposite to watch the people leave and go by. Dana may have been right, Parker decided as she felt a lot lighter after seeing Sophie and briefly catching glimpses of Nate, Eliot and Hardison in the audience. It was good to know they were safe and alive but she didn't think she could go back to them. Watching them leave as a group, Sophie clutching her note and looking around to see if she could catch a glimpse of her. Parker knew they were hidden however and that they wouldn't be seen. When they had scoped out the building they had identified the security cameras and evaded them, all but one which the kids avoided but Parker stopped under and looked up at and waved. she knew that Hardison would be checking the footage and that they would see it and hoped that them knowing she was safe and well would put them at ease despite the fact she wasn't returning.
For fun and to practice their skills they tracked Parker's old team back to the bar and then Nate's apartment over roofs and through the vents, the kids curious about who their adopted older sister used to work for and Parker satisfying her own curiosity. They saw them discuss the note she had left and watched the new case they were working on. For closure, Parker and the kids stole a few bits and pieces to help the team with their case that miraculously turned up where they needed it and Parker watched to make sure they all got out safely before she and the kids left. Parker had details of a new person to help and they wanted to get back in the game. That wasn't the last Parker would see of her old team though.