Well my first suggestion would be get the money to get them fixed. And she will stay in heat for 3 weeks bleed the first two and not bleed the 3rd week the 3rd week is the most susceptible to getting pregnant. Keep them in different rooms. But mother nature will always find a way. If you really can't afford to get them fixed them you really can't afford to have those puppies. And especially if she ends up having to have a c section that can cost you any where from $400 to $1500 . Hope I helped some
Get her fixed...I just had to do that with my dog.
You just have to take both of them to vet and strile them.
Some vets offer to spay and neuter going by income, you should call around and see if there is one in your area.