Brought my 5 and 3 year old children here after reading reviews. It was great for them. There was a park greeter there who helped me out and pointed me to the Bajada trail (a small paved loop with about 12 educational stations and some places to sit and rest). He was extremely pleasant and helpful and the Bajada Trail was great. Particularly the panoramic with descriptions of the area and the pictures of the wildlife.
Only downside as a parent of young ones are the "hard core" speed walkers / joggers who apparently try to set land speed records from the minute they exit their car in the parking lot. The first 100 yards from the Welcome Center to get to the Bajada trail is crowded on Saturday at 9AM. This shouldn't be a deterrent for other parents, just be mindful of the weekend warrior who absolutely has to sprint that first 100 yards.