It is important to make sure that Dad gets the opportunity to do more for her. We were having this problem with our 3 yr old this past year and slowly we started with more Daddy things. She risisted at first, and we had a few tantrums but she lived and so did we. I would warn her first so she didn't have a sudden "No, Daddy is going to do that". In your case I would sit down with her and talk to her about you feeling sick and Daddy needing to help with some things. Let her know that if you tell her Daddy will do something for her (get her snack, help her go potty, put her to bed, give bath...whatever) then either Daddy does it or she doesn't get it. For us it was morning routine since I'm a stay home MOm. She didn't want Daddy doing anything in the morning, not even give her milk or turn on the TV. So, the night before I would say "Daddy is getting up with you in the morning and getting you milk and Curious George, and if you don't let him do it then you won't get any milk or TV". We had to stick to it a few times (long tantrum and no milk or TV) but you bet the next time, she let daddy do it! It's worked with bedtime too "you let Daddy do books, or you go straight to bed without them", always with warning earlier in the evening so she knew it was comming. This will make it SO much easier once the baby is here.