my ratties

Question
Hi, i bought two male rats on august 14th this year from different litter one 7 weeks and the other 8 weeks.  they get on well and have a nice set up, and we love them dearly. the black one is called Sirius Black and he is most definitely a gentle male.the other rat (grey hooded ) Mr Norris is in fact a female!
the rats are 13 weeks and 12 weeks respectively. i have separated them-they still live in the same cage on different levels. i have spoken to my vet and i am taking Sirius for a pre op check- with view to castrating him so he can eventually live with Mrs Norris.The rats really miss each other and it is quite heartbreaking to think they may not be able to be housed together again. my 4 and 3/4 year old daughter is very upset and cross with the pet shop owner.
Mrs Norris is likely to be pregnant. she has started making a nest in her igloo and her behaviour is really jumpy- she is quite bitey and doesnt want to be handled. previously she liked to snuggle in my hoodie with Sirius and was fine being stroked. today she started squeaking and there appeared to be shuddering in her tummy? i need all the advice you can offer.thank you.

Answer
I am not sure what advice you are asking for?  Do you mean, if she has babies, or do you want to know about surgery?  Sounds like she is pregnant and the nesting is natural for a pregnant mother to do just before she has the babies. Gestation is 21 days.  Here is a great link for you to use to know all about new babies and how to care for mom etc....  Hope this helps.

http://ratguide.com/breeding/