RV parks in St. Louis, MO area (and between Austin and there)

[BigL]

May be making a trip to St. Louis later this summer and thinking of doing a family road trip along with it. Time wise is pretty flexible (up to 4 weeks). Any suggestions on places to stay on the way there and back and once we get there? Will have my family with me. Wife, 11 yr old son, 6 yr old daughter and 2 yr old son with me. So most driving in a day will be ~6-8 hrs.

Thinking of going into Tennessee & Kentucky on one of the legs of the trip.

[BigL]

Thinking of something on the lines of
Georgetown->Tulsa->St. Louis on the way there

On way torn on what to do. Thinking going into Kentucky or Tennessee but haven't figured out the trip home from there. Open to anything that direction. My shortlist is Louisville, Nashville, Memphis, or maybe even dip down to Huntsville, AL. Any suggestions?