heres the email i would send
hello its good you want to seperate up the babies and mum and dad after thier litter as you must be aware mum can be impregnated immediatly afterwards(the birth) i dont know if you have seen but there are hundreds of rabbits in rescues(just see rabbit rehome for proof) and it seems some breeders are breeding irresponsibly... now im sure you and your son(as at age 7 you must have to do all the work as we all know how easily kids get bored) arent one of them but.
just thought id offer some advice iv learnt along the way....
rabbits have to be in 6x2x2ft hutches with a minimum run size of 6x6ft which sounds big but as they need as much excersise of a small dog(and you can be prosecuted for not keeping rabbtis correctly due to new animal welfare act)
a good diet will help the babies grow strong and to help them suffer less from problems when they grow up they need to be with mum until at least 8 weeeks but not after 12weeks the boys in case they cause more litters(and inbreeding is very bad)
also to veryfy the genetics(and save yourself hundreds of pounds in vet bills) you need to trace back at least 4 genreeations to get good bunnies.
hoemchecking these days seems to get harder i know as so many people want to give them away cheap and dont think about the conditions they are going to a fact sheet from the rwa is a good thing to give out as it has al lthe info on the two vaccinations they need and worming to protect from ec and housing and food(pellets of higher than 16% fibre and hay80% with fresh veg)
also thought you might find it useful is about to get teh best kits out of your doe you shouldnt breed her more than 2-3 times a year as she can get complications.... oh and after age 3 they do need to be retired else can die giving birth considering if they are speyed after no longer being bred frrom(to protect form uterine cancer which kills 85% over 3yrs)(and male netuered) they seem to love settling down as pets of the family especially as tehy are so much easier to litter train and can live anythign between 8 and 14 years!
any way just thought with your son being new to this a few helpful tips might come in handy.... please feel free to email me if i can be of further help.