I am new to rat breeding and have a quick question for anyone with a little more exprience

I have 2 females sisters that have been housed together all their lives
Lucky birthed her first litter 6-25 4 babies and has been a wonderful mother
Lucy birthed her first little this evening 11 babies and well Lucky has taken all the babies and bedding into her nest and left Lucy sitting in the other corner of the cage no babies. Lucy doesnt seem to mind this and is relaxing after the ordeal of childbirth. My question should I seperate them out or leave them together and see what happens
Thanks in advance as always guys
Erik