we went to haggerston 2 yrs ago in May and it was so warm we spent loads of time at the outdoor pool. we had dd1 (who was 2 at the time) with us
there was lots to do, the only down side was the slot machines - full of young teens, really noisy etc, but you just do a sprint through that and you can get to the pool etc. at nighttime we would have our tea then head down to the centre - there is a little disco for kids and you can sit and have a drink while they boogie on down.
we ate once at the restaurant and it wasnt very good - v expensive for a shite menu - burgers or curry - that was about it. better to make your own in the caravan (because you have a gold one the facilities will be excellent and clean)
there is a supermarket on the site but use this for emergencies only - there is a safeway/morrisons on the main route heading north - 5 mins drive.
there are pedalos, trampolines, horseriding, loads of stuff to do
and about 15 mins drive (north) there is a fabulous farm called conundrum farm - v v clean with a gorgeous tearoom working farm where there will be lots of baby animals (lambs, rabbits, goats etc) for you to ooh and aah at. and you can feed them too
\link{http://www.conundrumfarm.co.uk/\if you only do one thing, make sure its conundrum farm!}