When your sister is invited into your kids’ club and you’re not, you know they’ve found a friend for life.

“Barbara [Pierce Bush] and my kids formed a glitter club, which I’m not part of because they think that I am going to be offended by the mess,” Jenna Bush Hager tells PEOPLE of her twin sister’s relationship with her two daughters Poppy Louise, 4, and Margaret “Mila” Laura, 6½.