Hon, I had one girl that didn't show until the last week of her pregnancy. I could have sworn she did not take but I kept her with me all the time just in case. She suddenly got a little 'bump' the beginning of the 9th week and had FOUR little ones. I was left wondering where she hid them???
I have one that starts showing at 4-5 weeks, you just never know. Is this her first litter?