A childhood belief about imaginary friends

When I was in fourth grade, I was reading a series of books called Animorphs. I was obsessed with them at the time, and one of my friends had started to read them too. She didn't know about them as much as me, since she had just begun, and I (of course) was an expert... soon we knew most things there were to know about them, and started making up that the characters in the book, which have the power to withdraw DNA from another living creature and become it, wanted to be our friends. It started out small, that we had seen them sneaking around looking "suspicious" and kind of watching us... then we talked to them.. and it progressed that they wanted us to become part of the group. Then we had the powers (we had totally convinced ourselves that it was real by then and that we had the powers) that they had, then stronger, then we were the most powerful beings in the universe, and we had to keep it secret. we were aliens, and we had our code because evil aliens called the "yeerks" were always after them... it went on for a couple of years.. then I was away for a year, and when i came back we had forgotten about it and didn't talk about it. Really funny to think of now.