He is about 10 weeks. He was supposed to stay with his mother for another week or two, but one of the other kittens died, and they found a mothersless litter, just a few days old, and mother Veerle accepted the babies. So her own kittens were let out of the bench, which they thoroughly enjoyed, and Veerle stayed in the bench with the new litter.
So, even at the rescue, he was no longer with his mother most of the time. But, of course, he could still see and hear her.
And he knew the other cats there, and he doesn't know our cats as yet.