Hi J.,
We went through this when we brought my dd, now 3 home and my ds was 5 at the time.
Maybe get some gifts for your daughter 'from' your new baby. Things she loves and can do alone...blocks, puzzles, etc. Also, let her pick out a special gift for the baby...a rattle, etc. Maybe getting her a very special new baby doll would help, they you could be taking care of your 'babies' together.
I would try to avoid more juice and TV, since both those can cause more problems, the extra sugar and the extra TV stimulation. But do give other goodies.
Also, this is a good time to reach out for help, especially while you recover from the C section. Let friends take her for play dates to the playground, etc. Getting her tuckered out may help too. And you give you some quiet time with the baby. Oh, and make sure everyone that comes around including dad make just as big a fuss over her (if not bigger) than the new baby, that will help her to not feel left out. I kept a box of small gifts wrapped so when someone came with something for the baby she got something too.
Good luck, it gets better with time too :)
S.