@kkk444,
I think you should find another provider. Several things bother me:
First of all, I don't believe you 'teach' a baby to sit... they will do this on their own.
Edit: babies can't sit up by themselves until their muscles are strong enough so they're insane. It's like trying to teach a newborn to hold up their head. Idiots.
And hey, too bad if baby expects to be held - that's normal for some babies... and are they not day care providers? They could put her in a chair and talk to her instead, or various other things, not try to force her to sit so they can be free.
Secondly, it shouldn't matter how long it takes to settle her and why should you have to pick her up because of that? Lots of babies are fussy and day care people should know that and take it in stride. And why should you have to
pick baby up because a) she takes a while to settle, and b) what has that new baby got to do with it??
I'm really not liking these people at all and I really think you should find a new daycare, one where they like having your child and you don't have to worry about all this crap.