Care and Feeding I’m trying not to jump to negative conclusions. Photo illustration by Slate. Photo by AHPhotoswpg/iStock/Getty Images Plus. Care and Feeding is Slate’s parenting advice column.  Have a question for Care and Feeding?  Submit it here . Dear Care and Feeding, Recently, my family visited a park we go to often. Our kids, ages 5 and 2, were playing when a group of young adults arrived with three children around the ages of 5, 3, and 1. These other parents were easily 20 years younger than my wife and me. Our kids usually love making friends at the park, so my son tried to join the oldest child’s game. She told him he couldn’t play, and although he was disappointed, he handled it well because we’ve talked before about how other kids can choose whether or not to join in. My younger daughter started copying the other kids’ digging game from a few feet away, not trying to join directly.…