Living nearby I can give you a little advice. You may want to drive a little to get a nice place. Jellystone in Portage is pretty much all seasonal. I've never stayed there. Indiana Dunes SP is good but hard to get into. Oak Lake Family Campground is nice but maybe a little too far for you. Michigan City Campground is nice but, again, maybe a little too far away. Most of the places that are somewhat close to Lynwood do not get good reviews.
Dan & Christine (and Molly)
2015 GMC Sierra 4WD Crew Cab Short Bed with Max Trailer Pkg
2015 Jayco White Hawk 27 DSRL