Can't remember the movie...?

Okay, all I remember about the movie is that these groups of mice go off on an adventure because one of them has to save a sick friend back home. I know it's not the secret of NIMH, because I just recently watched that and it's not the Rescuers or Stuart Little. There's singing involved and owls...and some birds who hold a funeral cause they think one of them is going to die cause they got stuck in the mud. It's driving me nuts that I can't remember the name. All I can remember is the little details and Google is no help at all!