Well, I'm stopping the litters after this second one. Dad's been removed. I've read many sites online from Europe that declare these rats to be incredibly welcoming of strangers of their and other species, I guess I'll be putting that to the test in the future.
Dad's going to be in with the boys in the next few weeks, as he's already been removed from the First mother as she gets ready to birth these next few days to avoid another pregnancy.