You should tell your sister to separate the male from the female now. As other members have pointed out, a female can get pregnant immediately after giving birth and it can put so much stress on her poor body it can kill her.
Yes, you need to have a substantial vet fund built up before you take in any of the pups. They can get quite expensive and they need vet care like any other animal.
No one "jumped at" anything. The two people who replied asked whether or not the breeding was intentional:
Which was met with the following:
Asking a question does not imply anything was "assumed." It's a question. To get more information. This forum does not promote breeding, and there is not a single indication in the original post that this was in any way an accident. Hence, the questions.
Sfailed and Twilight - You and your sister know more than the members here because you know this person outside of this forum. How about instead of you two throwing a hissy fit when members suggest that breeding is not condoned here (it is not) you just politely explain what was absolutely not clear from the OP?