Mother Moose, also known by the name, that was given her inside the Paltronics' files - Mother Moose v.2, real name being Marilyn Moose (in the files her real name is referred to as "Marilyn Moose v.2), is, as the name files should point it out, the new, updated version of the original character from the playhouse, that was created using the biotechnology - a technology found by Paltronics. Originally, she was supposed to be created after Percy Poodle v.2, due to her old version being on the right side of the stage, however, due to complications regarding her design, as she had both female and male moose elements, it had to be postponed and instead Charlie Cat v.2 was created, even though he was, originally supposed to be created the last out of the original cast.

The complications regarding her creation were mainly related to her having certain elements, which were typical for male moose and due to the fact, that female moose had no horns, so Paltronics had lots of worrying regarding the design - the main staff thought, that creating Mother Moose v.2 would fail miserably, however they still wanted to try, the other staff thought about "simplifying" her design, as in removing that part of her, however that idea was meet with backslash, as it was a part of her character and, even when they were aware, that the new versions wouldn't be 1:1 identical as their original counterparts, they still wanted to move the horns to her design, no matter if it would fail or not. There was also a small group of the staff, that would want to rather replace Mother Moose than experimenting with making the main "core" of the design be identical, however those voices were also meet with backslash, but not as much as with the thought about not attempting to make her have that part of her.

The finale of solving the issue was to modify the DNA of female moose, giving it some of the parts of male moose DNA, which was risky, as not only they didn't do it before (Percy Poodle v.2 and Charlie Cat v.2 didn't need extra DNA modification to come out, however Mother Moose needed it). However, the operation was a success and due to it Mother Moose v.2 was created.

Paltronics was observing her, due to them being afraid, that evem if she did come out as intended, she could have some sort of problems, due to the whole DNA modification, but after a while they calmed down, upon realising that she was created as intended. However, they still needed to know, what was her personality, knowing damn well what happened with the original Charlie Cat's personality - it kinda disappeared.

With her personality, most of the Mother Moose v.1 was kept, as in being a caring person, her being friendly and her wanting to take care of kids, which her original version did do during the open days of the playhouse (the playhouse was closed for some time, due to the experiments and due to the need of remodelling), however, what did interest the main staff was her interest in psychology - she got invested into knowing more about the deepest parts of minds of people, she wanted to know how the mind EXACTLY worked, she wanted to know how it would work after various circumstances etc., which didn't worry them as much as how Charlie Cat v.2 didn't want to be the clown. So, they did give her some books that one of the staff - Samuel Samson had and she was reading it... And reading, and reading, getting the basic knowledge of the hidden enigmas of the mind.

Another thing, that got the staff interested was her relationship with Charlie Cat v.2 - unlike the original versions (versions 1, as written inside the Paltronics' files), she seemed to feel happy around him, she didn't really get into fights, and even if she did fall into fights, they would try to solve the problem. She seemed to be interested into his jokes, she even suggested him to make some jokes about the mind of humans, due to her having a basic knowledge, thanks to the book she got from the staff. The original versions' relationship with each other was WAY more chaotic, as they were programmed the way, that Mother Moose v.1 would often tell Charlie Cat v.1 to be careful, to not try his "pranks" on children, as they could get scared etc., but Mother Moose v.2 and Charlie Cat v.2's relationship? It seemed to be way more natural, due to the whole point of the project - having characters act more natural. The problem with Charlie and Marilyn's relationship was related to her original version having close relationship with Farmer Felix - they were dating, even, they were "wife" and "husband", but Paltronics had to get ready for the potential scenario of Marilyn Moose v.2 being in love with Charlie Cat v.2. About her relationship with Percy Poodle v.2, their relationship wasn't exactly like "Mother and son" type of relationship, but was more like a normal friendship, but sometimes Percy v.2 would, accidentally, call her "Mother", which could either be related to him still seeing her as a "mother" or because of her nickname.

After the playhouse reopened, with everyone being created, things seemed to be okay, as that version of Mother Moose seemed to get more kids around her, as she was WAY friendlier, was natural, and she knew, somewhat how to take care of kids, who would try to bully other kids, due to her knowledge in psychology. However, as it was mentioned before, something changed and the playhouse became a "missinghouse" or "mysteryhouse", as it was written inside the files - people were missing, but what was weirder was that only adults would go missing, no kids... Just like if only adults were capable of going missing...