Congratulations They are adorable and in such good condition. Even your mother cat looks well enough. Initially I just saw the first 2 lines, watched the video and straight away realised as the owners you’d have been so flat out. Topping feeds, even at some stage probably helping stimulate their bladders, keeping kittens at their extra early wanderlust stage confined and near enough so mummy cat was able to supervise and not be stressed by that.Plus balancing the assistance mum got with keeping her involved. Then ensuring she ate and especially remained hydrated enough. Then the massive litter use to clean by a food factory mother cat, and later so many kittens using litter and their misses that can occur when so many of them. The monitoring which still goes on. Probably trying to encourage kittens to eat and move towards weaning for mummy cat to sooner regain her optimum condition. Plus the kittens just adamantly keen to suckle from her as their first choice. Plus the vet check and immunisation start.