Christie Brinkley will always be her ex-husband Billy Joel's "Uptown Girl," and she's got a way of still supporting him.
The model, who recently celebrated her 70th birthday, stepped out in support of both the "Turn the Lights Back On" singer and their daughter, Alexa Ray Joel, 38, who joined her dad on the stage for his monthly Madison Square Garden concert.
The former couple were together from 1985 to 1994; she then married Richard Taubman for a year, with whom she shares son Jack Paris, 28, and later Peter Cook from 1996 to 2008, with whom she shares daughter Sailor, 25. Billy later married Food Network star Katie Lee Biegel from 2004 to 2009, and in 2015 married Alexis Roderick, with whom he shares daughters Della Rose, eight, and Remy Anne, six.
Over the weekend, Christie took to Instagram to share a sweet video of her ex's latest concert, during which their daughter Alexa took to the stage to perform a father-daughter duet of Billy's 1976 hit "Say Goodbye to Hollywood."
The clip sees Alexa taking the lead, singing into the microphone while wearing a 60s-esque, red flowy dress paired with white pumps, while her dad sings along and plays the piano.
In her caption, Christie endearingly wrote: "Say hello to my talented Ray of light, she's up there singing with all of her might," adding: "She got her talent from her pop."
Rhyming and making nods at some of Billy's most famous songs, she continued: "When they sing together we don't want it to stop. We're always in a New York State of Mind, 'cause at MSG we're feeling fine!"
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She then revealed: "And BTW she's got something up her sleeve… she'll be announcing soon so do not leave, keep checking here cause I can't keep mum," teasing: "It has something to do with pianos and drums!"
Christie affectionately concluded with: "Way to go Billy and Alexa Ray, listening to you just made my day!"
Alexa took to the comments section under the post and replied: "Mom, you are my ray of sunshine forever… I love you more than you could ever know," as fans of the family followed suit with plenty of compliments for her.
It has been a couple weeks full of celebration for Billy, who recently released his first single in nearly 20 years, "Turn the Lights Back On."
He performed the instant-hit for the first time at the Grammy Awards on February 4th, which he attended with his wife Alexis and their two adorable daughters.
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