I would think so, but I don't know 100% for sure.
Can My Eight Month Old Male Dog Get The Mother Dog Pregnant?
Yes he can, so now would be a good time to have the mother spayed.
Yes, As soon as the are able to be sexually active they are able to reproduce, It doesn't mean that they will on the first time but it is possible
Yes, a female in season should be kept away from males four months of age and up and of course there is the whole mother son thing and the higher risk of genetic defects showing up in the pups at some point. Is this also the same girl who is too old and may be pregnant for the third time in a row? You should spay her asap. Good Luck.
It is possible to get her pregnant as soon as they turn 4-6 months old