K.E.
Hard to answer....Is she a good sound sleeper in the sense that you can make a lot of noise and she doesn't wake? My daughter is a wonderfully sound sleeper. I've always made lots of noise when she's sleeping so that I wouldn't have to worry about her being a light sleeper. My sister was here this weekend with her newborn and my daughter slept through the cries. I worried about her waking because it was a new sound and I thought it might startle her or concern her, but she did really well with it. We're due in September, so I hope when we have a newborn here 24/7 she'll be the same.
Good luck!