Matthew McConaughey marked his mom Kay's birthday with a sweet Instagram post celebrating her 90th year
Matthew McConaughey and mom Mary Kathleen McCabe arrive at the Los Angeles Premiere of "The Lincoln Lawyer" at the ArcLight Hollywood on March 10, 2011 in Hollywood, California.
Credit: Gregg DeGuire/FilmMagic

Matthew McConaughey is celebrating his mom's milestone birthday!

The Sing 2 actor, 52, honored mom Kay on Instagram Friday when he helped ring in her 90th birthday. McConaughey shared a photo of Kay smiling while wearing a birthday crown and sash reading, "90 & Fabulous." 

He wrote in the caption, "Ma Mac McConaughey at 90 today— livin on joy, forgiveness, resistance, and 'not being able to imagine not being here.' - Happy birthday mom."

Kay recently moved in with McConaughey, wife Camila Alves McConaughey, and their three kids — Levi, 13, Vida, 11, and Livingston, 8 — during the coronavirus pandemic.

She opened up about quarantining in Austin, Texas, with her son and his family on a 2020 episode of Red Table Talk, calling the experience "really, really lovely."

"I'm enjoying so much being around my grandchildren. I'm very comfortable with them," she said at the time. "Matthew is a very good son. I tell him that all the time. He's good to me."

McConaughey shared his own take on living with his mom while speaking to The Washington Football Team that same year. During a virtual chat as part of the team's schedule release party, the actor shared, "We're good man, we're down here in Texas. We've got my Mom over here, she's 88, I cannot keep up with her!"

He added, "I've got three kids, they're redecorating rooms. I'm getting to know my pets better. I know where the water main line is on the property now, and I didn't know it before. I know a whole lot more about my house and my family than I did two months ago!"

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Alves McConaughey, 39, often posts videos of herself and Kay on social media, giving fans a glimpse into their sweet relationship. To mark Kay's 90th birthday on Friday, she shared some cute clips, including Kay's floral arrangements, balloons, and plastic flamingos.

"Cheers to the woman who always tells it like it is, loves a good glass of Chardonnay, and keeps us all laughing! Wishing you a very happy 90th birthday, from the entire #WomenofToday community 🎉 #MaMacTurns90 #90AndFabulous," she wrote.

Alves McConaughey opened up to PEOPLE about living with her mother-in-law in 2020, sharing that the two had been spending plenty of time together, including cooking meals in their Austin kitchen — although she admitted that Kay is more of a "taste-tester" and less of a chef.

"I love that my mother-in-law is lighthearted and helps to keep the laughter alive when we're together," Alves McConaughey told PEOPLE.  "Her feistiness, positive attitude and confidence at 88 years old is a daily reminder of mind over matter and that is so important during these times."

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