I recently went on a girl's weekend to San Francisco with my aunts & a few cousins on my mom's side. My mom has a lot of siblings/sisters and it's become a bit of a tradition that when one of the sisters turns *a certain age which I will get in trouble for specifying*, they go on a trip together and cousins are invited as well. Although we've learned that we get the invite purely so we can take photos of them and handle ordering Ubers.
