And now she's posted pics online of a Hamptons fishing trip with her daughter Alexa Ray Joel - and they could definitely pass for sisters, too.
While Alexa, the daughter of Christie
and Billy Joel, showed off her curves in a white halter neck bikini, Christie went all nautical in a blue and white striped number and navy shorts.
She posted the pics on her Instagram account, writing: "It's no fluke that we're having fun... Cause we're together on the water!"
The 59-year-old's son, Jack Brinkley-Cook, also joined the family fishing trip. Christie
uploaded a pic of his catch, writing: "Jack caught a DOORMAT!"
The whole crew also posed for a pic at the end of the trip and the age-defying mum wrote: "Thank you Captain Peter Van Scoyoc Dream Catcher for a picture perfect day!"
Who'd have thought a fishing trip could be so glamorous?
See more stars and their mums below: