Hello guys/gals/theys! I'm just gonna cut to the chase. Okay, so, I've been seeing some VERY heated (NOT LIKE THAT) that the toys from Poppy Playtime are possessed by children souls, like FNAF, and those souls are still kids by the time the Player returns to the factory. Yes that is half true, because the higher ups were experimenting on the children. However, it has been confirmed that the toys are NOT possessed, they are flesh and bone, this has been shown over and over again in the game and in VHS tapes on Mob Entertainment's YouTube channel. Like when Huggy Wuggy 'tripped' into the abyss.in Chapter 1,when puddles of blood were around small dead toys in each chapter, when Ms. Delight was crushed by a door and Catnap was impaled in Chapter 3.
I will use Catnap as an example. So, we know Catnap used to be a child named Theodore Grambell, he was 7 years old at the time. It was confirmed that Theodore's operation took place in 1987. The Hour of Joy took place on August 8th, 1989, so Theodore/Catnap was 8 years old when the Hour of Joy happened. We, the Player, returned to Playtime Co. 10 years later, in 2005. So, that would mean that Catnap/Theodore would be around 18 years old.
Keep in mind that all of this was confirmed in the game, in VHS tapes, and by Mob Entertainment themself. So, if the words of the developers aren't enough for you, then I don't know what is.