Getaway for family, 2 little ones

Hello all, Central Valley invader. I promise I’m civilized. My wife and I have 2 children (2/4) and would like to escape the Fresno heat. Looking for a place that is:

Less crowded Family friendly Relatively walkable Things to do for the little ones.

I have been to Pismo dozens of times (Spent many summers and other school vacations there with relatives in Oceano). Went to Avila last year, enjoyed it. Unfortunately, those cities are ones my wife wants to avoid this time around.

Thanks in advance.