Many American Beyoncé fans traveled to see her "Cowboy Carter" tour in London, despite her U.S. stops. Here's why they say it's worth it.

Midway through the performance, the pop superstar quickly paused to wish her twins, Rumi — who joined her mother on stage — and Sir, a happy birthday. “Everybody say happy birthday, Rumi,” Bey told the obliging crowd, while 13-year-old Blue Ivy lovingly cupped her little sister’s chin.

Z’s youngest kids Rumi Carter and Sir Carter the spotlight during her Cowboy Carter tour stop in London June 12. See how the crowd marked her twins’ birthday.