Leg Control

When i was at the physio a few weeks ago with Eleanor they where worried about her leg development as she doesn't push up with her legs when you stand her on you and also curls her toes more on her left foot.

I know Alex had great leg control at a very young age but Eleanor has none.

I've been using a Jollyjumper to help but she still won't use her legs when you try.

The other thing they where looking at was the fact she doesn't roll and won't go into the crawling position.

Should i be worried about this ?
What else can i try i was thinking of a walker but DH says no as i didn't use one for the other two but Eleanor isn't like the other two where.