Christie Brinkley will always be supportive of her ex-husband Billy Joel, as will her daughter Sailor Brinkley Cook!
Over the weekend, the model stepped out along with her daughter to support the "Uptown Girl" singer – for the second time this year – and their daughter Alexa Ray Joel, as they performed together in Madison Square Garden, which Billy does once a month.
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.
Following the extra special concert, Christie took to Instagram to give a special shout-out to both Billy and Alexa, sharing a video of her and Sailor standing in the arena section, excitedly singing a variety of his hit songs, from "Piano Man" to "The Longest Time."
"Thanks for singing us a song @billyjoel and @alexarayjoel. You've got us feeling alright!" Christie aptly wrote in her caption.
"Just a few snippets from a magical evening at the garden!" she added, joking: "Sometimes with my thumb over the speaker my apologies," and: "@sailorbrinkleycook I must add we were pretty good back up singers right?"
Sailor took to the comments section under the post and declared the family outing to be the "best night ever!!!!!!!!" as fans then gushed over Christie and Billy's continued friendship even after their split 30 years ago.
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"Total classic act. So awesome how supportive you both are of each other," one wrote, as others added: "You and Sailor were having a good time! Love how you support Billy, and the video of Alexa singing to her dad is so beautiful," and: "How fun!!!!! Alexa singing with her dad, her hero, is priceless," as well as: "Looks like a fantastic evening! What a thrill it has to be to see your baby girl up there with her dad."
She followed up her first post with another featuring clips of her daughter Alexa singing, and wrote: "Before @billyjoel's historic residency at @thegarden becomes a souvenir that slowly fades away… one more night to remember!"
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"Alexa Ray and her Pop in perfect harmony on, 'Say Goodbye to Hollywood' one last time in this great huge arena that Billy has turned into his own cozy living room," she continued; Billy's residence will come to an end in July with his 150th show.
Christie concluded: "And then as if that charming duo wasn't enough, the tears welled up when she surprised her dad with a serenade of 'To Sir With Love' (technical difficulties on my video so not pictured) but trust me it was sweetness personified. Billy was in his word, faklempt!"
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