My new dog has very saggy teats, and my new puppy…?

Tries to s**kle from her!!! http://i244.photobucket.com/albums/gg37/chalbri/P6292725.jpg
(pic of her saggy teats– she needs a lift & tuck!)

I just adopted an AmStaff puppy today (Lollipop,) they think she’s about 7 weeks old.

My other dog, (Daisy,) was just spayed last week Monday, and had 3 lumps removed from her nipple-area. (She had puppies before we got her!)

Should I just let them play together? I’m worried that Lolli might hurt Daisy when she tries to nurse from her– she has 4 little incision sites. I’m sure Daisy would let Lollipop know if she was hurting her…. BUT should I keep them apart for a while?