My father is 14 years younger than the next oldest sibling. My mother is 12 years younger than the next oldest sibling. Because of this my cousins were all much older than me and not people I interacted with. My little brother, my only sibling, is 14 years younger than me. My oldest is 11 and by the time my brother does have kids, if he has kids, my children will be probably be close to adults.

Fortunately my ex-wife has a lot of cousins she is close to and her sister has a daughter right in the middle of my 2 kids so they have 1 first cousin they are very close with but they have no interactions with second cousins outside of seeing them every few years at holidays.

Regardless, having no real interaction with my cousins growing up, I can't say if my life would have been better if I had.