Her jealousy is a sign of how close you are. She sees no reason why she should have to share you with anyone including her dad! That's normal thinking for a toddler.
The best approach is to reassure her that you love her very much and that nobody will ever replace her. That gets at the core of her concerns. The worst thing you or your husband could do is to become angry with her, since that will only make her more anxious and jealous.
By the way, you can expect her attentions to shift back and forth over the next dozen years. In a year or two she'll become "Daddy's girl" and act as if you're an intruder in the family. Again, that's perfectly normal. So enjoy the times when you're the focus of her life, and reassure your husband that his time will come soon.
