Re: walking baby animation query.

Hey there
Dont know if this will help but try this :
1. make your baby animation in a new comp.
2. render it as a movie file
3. import that movie into your original comp
4. (now I'll try to make this sound legible) with the movie layer highlighted click on effects & presets -> Keying -> color keying. Then use the color dropper nad select your movie clip. Viola! you just have made your background of your movie transparent.
5.now right click on your movie in the project panel. Interpret footage -> Main... then enter a high figure on the loop box.
6 you will now see on the timeline the fle is extendable
hope that works