Haven't been for a few years but we found Bromyard Excellent with kids, as it is all on one site.
Miskin is good too, if you are camping you are on site but if you are in a caravan or camper, the site is a few hundred yards up the road, we took it in turns to babysit in the evenings, when they were bigger, but our kids used to sleep through most sessions when that age till the wee small hours under the table!
Cheers Lucy