There is an animated movie from the seventies or eighties I've been looking EVERYWHERE for but can't find(it's REALLY obscure). Basically the premise is that this old women dies and leaves everything she has to her pets and her twin nephews try to steal it from them. It's basically a "main characters fight for what's theirs'" movie. I just need the title.

Sounds like Millionaire Dogs [1|9] - YouTube (http://www.youtube.com/watch?v=IhzFBYlNx9s&feature=relmfu)