
Hi taggabags
It happened to me a couple of years back. One of my maiden girls had her first litter of 2 pups and was fully recovered well before her next season (which she was NOT mated on.)
The vet said that it wasn't so much the carrying of the litter that dragged them down but the rearing of large litters, so put that down to her regaining fitness so fast.
He agreed that he had no problem for her to be mated on her next season (after her resting season.)
She came in early. So her first litter was born at the end of January, and her second litter was born early January of the following year.
So when people talk about breeding bitches too close together, I think you need to know the background. My girl had 2 pups both times (which were for me), and I had no problem with registering them. I don't think that I was overbreeding my girl, and I see no problem with you registering 2 litters that didn't quite make the 12 months break.