India, June 14 -- Beyonce took a moment during her Cowboy Carter concert in London to celebrate a special day for her twins, Rumi and Sir Carter. While performing "Protector" on June 12, she hit pause and got the crowd involved in wishing her kids a happy 8th birthday.

"Everybody say happy birthday, Rumi," Beyonce said, as Rumi held onto her mother. Big sister Blue Ivy, 13, was also spotted looking on lovingly at her younger sister.

Then came a shoutout for her son (Sir Carter): "Say happy birthday, Sir! Mommy loves you," Beyonce added, and the crowd cheered just as loud.

Fans were quick to react to Beyonce's on-stage moment with her kids.

A fan wrote, "I love their family.. so cutie."

"Pure joy! Nothing beats a mom's love on stage,"...