Christie Brinkley is nothing but supportive when it comes to her ex-husband's fourth marriage. Brinkley's ex-husband Billy Joel recently married 33-year-old girlfriend Alexis Roderick.

NZ Herald reported that the gorgeous 61-year-old attended the ceremony. Brinkley even posted a photo of the newlyweds on Instagram and she captioned it: "Congratulations to the glowing bride and groom. And to my daughter Alexa, who has a wonderful friend in Alexis! Wishing the growing family every happiness!"

Although Brinkley's message is thought to be a "class act" by many, there are those who view her message as a subtle and indirect reference to the fact that Billy Joel's new wife is almost the same age as her daughter.

Page Six has learned that Billy Joel's longtime girlfriend Alexis Roderick is only four years older than his daughter, Alexa Ray Joel. 

Daily Mail reported that a spokesperson for Christie Brinkley said that she didn't have any underlying motive in writing the post. The statement was said to be Brinkley's way of sending well-wishes to Billy, who remains to be a close friend, and his bride, Alexis.

The spokesperson went on to say that Christie genuinely cares for Alexis, adding that that even Brinkley and Joel's daughter Alexa loves the new bride as well. It was a happy and loving event and her Instagram post reflected that sentiment.

Alexa is Joel's only child, but that's about to change because the newlyweds are expecting a baby girl. The guests were not told that there was going to be a wedding. They thought that it was just the usual Fourth of July celebration but it turned out to be a "surprise wedding."

The couple had been together since 2009 and sources close to the couple said that Billy Joel is excited to become a father again.