I think the title says it all! We're looking at a midweek/week long break in march just before Easter hols kids will be 11 months and 3 years. Needs to be somewhere with indoor activities and comfy accommodation as the weather no doubt will be dreadful!
Looked v nice, having done centre parcs hot tub lodge v's hoeseasons ones, I'd pick hoeseasons every time! Didn't actually stay in this one as we went North England instead but looks v nice and has 'go active' which seems v c parcs like..
Not southern England, but have you thought about Bluestone in Wales? It's near Saundersfoot, set in fantastic surroundings, and loads to do both inside and out, and away from the park too. Great for children of all ages.
I have been here and think the activities are fab. Having said that I would say that the accomodation is 2* (notice no pictures but there are some on tripadvisor) and the food is quite canteeny. Lots of people rave about it on Tripadvisor but they also get the criticisms as well. Might be good for you and might not - only you can decide. Most activities included in the price apart from a small charge for materials. http://www.manorhousehotel.co.uk/