You will hate yourself for having paid money for this.
I hate this game with all of my heart. She loves it. I think the reasons she loves it so much are the reasons it makes me want to injure children.
First of all, it takes no brain to play this game. You seriously could glue a potato to a Wiimote and beat this game. It's almost as easy as watching a movie. A movie that lets you pet fish.
In addition to the lack of difficulty, there's also an absence of plot, character development, conflict, and substance. You know, the things that make up the foundation of books, movies, games, plays, stories, etc. I'm sure you get my point.
I think the reason she likes it soo much is the fact she doesn't have any resistance in the game. She can just waste hours petting clownfish and staring at jagged ocean scenes listening to some banshee wail to some electronica music.
I guess this is one of those niche games. For stupid people (no disrespect to my mother of course) who have plenty of time to burn, I highly recommend it. For anyone with any appreciation for quality games or thier own sanity or dignity, stay the hell away.