The "Wife & Toddlers" bit leads me to think of two we've been to…
Pear Tree Park in Dorset, has caravans on some bits but the lower tent area is really superb. Kids loved it. Huge pitches, plenty of shade etc. Really nice atmosphere
If Devon is more your thing, then ironically the Caravan Club site at Hillhead has a superb tent field, nice level grass, banking all around to sheild the wind, & some nice views out to sea. Facilities are about as good as you'll find with excellent family shower rooms & baby/toddler rooms with small baths etc. Excellent heated pool & pub on site. Caravan Club standards are pretty high & place is kept spotless. You dont have to be a C.C member to stay there, but if if you become me for your stay you should get a discount. 😉