But this week they made a surprise appearance in a video shared on social media. The Black Parade hitmaker and her three-year-old children were seen sitting on a buggy on holiday, with Rumi smiling at the camera, while Sir looked away.
The short clip was posted on Instagram by Beyoncé's good friend and former stylist, Manuel A. Mendez, who has been working as the star's children's stylist since Blue was born.
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In the caption, Manuel wrote: "How adorable is this Clip? Rumi is too cute and Sir is giving me, no pictures please. Wearing a @minirodini matching tracksuit from head to toe."
Manuel previously opened up about his incredible job working with Beyoncé and her children during an interview with HELLO! and sweetly likened Blue to his niece.
Beyoncé's twins Rumi and Sir with their famous mum
The talented stylist has a close bond with Beyoncé's children and often shares posts about his job on social media, including a sweet clip of Sir dancing with his mum in the garden while filming Black is King.
While Rumi and Sir haven't made as many high-profile appearances as their older sister, Manuel has already started putting together outfits for them too.
"I've already started in past occasions helping mom and dad with day to day outfit proposals," he said. "I would love to help curate red carpet looks as well. You will have to stay tuned and see."
Beyoncé is a doting mum to twins Rumi and Sir
Award-winning singer Beyonce opened up about motherhood during a rare television interview on Good Morning America in 2019.
She said: "Being a mother, my family is my biggest priority. It's not many films that the parents can come and feel the way I feel about The Lion King, and feel that and pass that legacy onto their kids."
The award-winning singer with oldest daughter Blue Ivy
She also shared her surprise at finding out she was expecting twins in her Homecoming documentary in April 2018, which reflected on her headlining Coachella.
The Formation singer said: "I was supposed to do Coachella the year prior, but I got pregnant unexpectedly. And it ended up being twins which was even more of a surprise to me."
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