Some advice needed...

One of our girls, Tyrande has just (2 days ago) had quite a large litter, 16 of them to be precise. Quite a shock for our first foray into rat breeding after keeping them for years. What concerns me is that she keeps on splitting the litter up and hiding them in 3-4 groups around her cage, somethimes even burying them deep in the bedding. Just wondering if this is normal and safe? If not what, if anything can we do to discourage her.

Any advice gratefully received.