Blue Ivy Carter has taken to social media to share a joke with fans in an adorable post on Instagram by grandmother Tina Knowles.

The seven-year-old, who is the daughter of music royalty Beyonce and JAY-Z, has made occasional appearances on Tina's channel, and showed up on Sunday (24Mar19) for her grandma's regular "corny joke time" segment.

While Blue did not show her face, she waved her hand in front of the camera and said "hey" when the fashion designer, 65, introduced her "beautiful granddaughter."

After she admitted that the joke she was going to share came directly from Blue, Tina invited the youngster to tell it herself, to which she happily obliged.

"How many lips does a flower have?" Blue asked from behind the camera, as the House of Dereon founder replied, "Well how many?"

"Two lips – get it? Because there’s a flower called a Tulip," she quipped, as her grandmother said "I got it, I got it," with an appreciative grin on her face.

Blue is the eldest daughter of the Run The World hitmaker, 37, and rapper husband Jay, 49. The couple also share twins - a daughter, Rumi, and son, Sir - who were born in 2017.

It's not the first time that Blue has left fans giggling on social media, as she scolded Tina in May (18) for filming in a French theatre when she wasn't supposed to.

The matriarch subsequently shared the video on social media, in which Blue could be heard reminding her grandmother that taking video was against the venue's rules.

"You're not supposed to take videos grandma," she insisted. "You're not supposed to."