Let me be clear: Teresa is not an only child. At 3, she is the much-loved younger sibling of a significantly older brother and sister. But in many ways, she’s on her own. There’s no one in the house who shares her interests, no one near her age to negotiate with over the use of toys, even to fight with over who gets to choose a bedtime story. Her toys are her own — Caroline, 15, and Frank, 12, really aren’t interested — and they’re often the ones reading her stories, not joining her in being read to. Enter the cousins. My sister has five children, ranging in age from 9 to 1, including Zoe, 5, and Megan, 3. When she is with them, the three become a pack known as “the little girls” — to differentiate them from 9-year-old Skylar and, of course, the boys, Billy, 7, and Henry, 1. They walk holding hands, they giggle, they dress up, they trade clothes and generally have a fine time. Sometimes they even fight, over who is going to ride which bike, or who is going to use which scooter, over who gets the Dora helmet and who gets the Little Kitty helmet, which is a revelation to Teresa. She’s not used to having anyone who will engage in an argument with her, let alone be close enough in size to share bikes or helmets. I watch my sister’s kids and marvel at how well they function as a unit; visit a zoo or a museum with them, and watch them stay together! And watch Teresa wander off to look at anything that catches her eye, because after all, when we take her on her own, we don’t particularly care what we look at, and she ends up setting the pace. My sister has my unending respect for teaching them how to behave in public well enough that grocery shopping with five little ones in tow is even possible, let alone a regular occurrence. Sure, Teresa behaves herself in stores, but it’s not as hard when she can sit in the cart at Target, hands well away from the merchandise, and I don’t have to worry about keeping track of anyone else. What I find most heartening is the care the cousins show for one another. After our last visit — when Zoe had twin Band-Aids on her legs from immunizations earlier in the day — Teresa wanted to know the next day whether Zoe’s boo-boos were better. My sister jokes that we have to get Teresa a phone, because her kids are always asking to call Teresa and invite her on their adventures. Teresa will start preschool in September, and I think that she will have an easier transition because of the time she has spent with her cousins. Experiences like swimming and skating lessons, when she must accept the authority of teacher, also help, but they don’t always offer the opportunities for free interaction among children that she will have at school. Thank God for cousins.