Camping spots are spacious but fill up quickly for the season. Boating, fishing, and lake swimming/beach area are great. The bath houses have vault toilets. Many weekends they have live music and/or activities for the family. Local officers patrol the area during busy weekends and the park is staffed at the gatehouse 24/7 where ice and firewood is sold. Playgrounds, basketball court, and plenty of open space for other activities. They also have boat rentals now!
My family has stayed at Sullivan Lake many times. It is an awesome place to go for a family outing. They have all kinds of camping sites, a huge lake that can support all sizes of family boating. A beach for swimming. Pets are welcome. Check their site for events.