In the comic adaptation of episode 2, Mimi refers to herself as Scooter's "little sister" twice. Not only is she a year older than him, but she makes such a big deal about it more than once...granted, she could've been going for the sympathy angle, but it still strikes me as odd.
She fell through a time loop off screen and complicated things.
Did anyone else first think Chu Chu was a cat on looks alone?
Not me, but I'd read that he was a dog. I can see how anyone would make that mistake if they were going into the series blind.