bound to be a little. Your daughter is soon to have her personal space and time with you irrevocably changed ! Probably best to say that your daughter is the big sister and that means having to learn to be patient. Also that her brother/sister needs them to show them how things work. Daddy needs her to help him look after you. You should say the same about daddy.
Tell her to repeat this over and over: "this is my sister. There are many like it but this one is mine. Without my sister, I am useless. Without me, my sister is useless."
I think a lot will depend on if she has a sister or a brother. I remember my brother being such a pest but we bonded well as we grew older. Eventually he became my protector.
We were lucky never really had it with ours - older boy and 5 years difference. Due to the age gap I'd expect it to be less of a problem than I've seen in my extended family when the siblings are closer together in age