The Wednesday actress took to Instagram with a message and video to celebrate her 20th birthday.
Alongside never-before-seen family videos - which can be viewed below - Catherine wrote an emotional message to Carys.
"20 years ago today my daughter Carys came in to my arms and there is not a day I haven’t cherished," she wrote. "Happy Birthday beautiful lady."
The birthday girl wrote back and commented: "Thank you mommy! I love you so deeply- thank you for the wonderful mother you have been for these 20 years."
The video featured a clip from Carys' childhood and had fans all choked up. "Cutest mother and daughter duo," wrote one, while another added: "She’s the spitting image of you."
Michael also wished her happy birthday on social media and wrote: "To my darling daughter Carys, wishing you a happy happy birthday! Now that you are leaving your teens, may this be a wonderful New Year for you darling! I love you! Dad."
Catherine and Michael also share their son, Dylan, who turned 22 last year.
Both children have grown up in the spotlight but their famous parents insist they've kept them grounded. At one point, Catherine revealed both her son and daughter wanted to follow in her and Michael's footsteps and enter the entertainment industry.
But now, it seems they're both looking at an alternative career path. Speaking to Parade in December 2022, the Welsh actress said: "They’d love to join the [acting] business! My son has done theater production since high school. They’ve both been to drama camp."
She then elaborated and revealed: "But they also love learning and are history buffs."With acting being just one of their passions, what else are Carys and Dylan interested in?
"My son graduated from Brown University this year and he studied political science," Catherine added."He’s doing internships and working on political PACs."
And as for her youngest? "My daughter is currently studying foreign relations and diplomacy at school. They got their brains from me, though my husband likes to differ," she quipped.
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