Help my rat had babies and Im not sure which one is the mum

Question
Ok I had two female preggo rats that I got from the pet shop.  I have a very badly need question answered how can I tell which rat is the birthing mum.  Is no sqeaking a good sign that they are eating?  I know that one or both gave birth about 2:30am this morning.  I didn't want to bother them but when I seen the mum (star)on the top level I got worried and thought I would take a look. I seen two different piles of babies. My other rat (curlycue) was sitting on one and I didn't think she gave birth because her nipples arn't showing yet and then the other pile where star went to and attended to. Is it possible for a preggo rat to steal and then try to nurse the newborn babies? They are no fighting between to two females infact both seem happy. I did notice that curlycue seemed smaller.  The reason why I asked is because I wanted to seperate them asap. because i heard that one mum would snatch babies fro the other mum. but would they both have to be mums?  I do hearing sucking sounds and no sqeaks is this a good sign?  How can I check on the babies without stressing my females out.  the igaloo that they are under is one that you have to lift up to see what's under and it's size is a medium.  Any advice would be helpful.  I'm worried and excited at the same time.  Don't worry both piles seem to be small so if the babies servive and I can't find good homes for them they will all stay with me.

Answer
Hi,
At this point, I would not disturb the babies or the mother. They could turn on the babies and hurt them. For now, I would just keep watch and when the mother becomes apparent, I would take out the other female. If they both had babies, then I would just allow them both to nurture them. No noise may be a good sign, but you won't be able to tell until the babies surface.
Ann