There is a decent rv park on W. Jayne (main road off I-5 to Coalinga) just west of I-5. About 30 minutes to Lemoore NAS. North is Fresno and there is no place to stay there without armed guards.
Can't your son in law get you in the rv park on base? I'm retired AF reserve and usually a GI can get you on the CG, especially if they're going to be staying with you. (wink, wink).
Lemoore isn't exactly a destination resort but has a very nice rv park.
Their number is 559-998-0837 or 0838.
Website says they allow guests.
Website is militarycampgrounds.us