S.B.
I had the same problem when I had my baby! My son was 2 1/2 when she was born and I didn't know what to do!! I had everyone tell me to let him stay with them and they would bring him home in a couple of days!! I couldn't do that. I had my sister bring him to the hospital while I was in labor and see me! And as soon as she was born he was brought back in to see his new sister! Everyone wanted to take him home that night but I let him stay at the hospital with my husbad and I. When we came home I included him in everything I could so he wouldn't feel left out! He would get diapers, wipes, ect. He helped at bath time. He even would try to help feed her!!
I think as long as you try to include her in everything she will do better than if you send her away as soon as the baby gets here!! I waited almost a month before I would let anyone take my son. That way he knew the baby was here to stay and would still be here when he got home!! I wish you luck and hope this helps!!