Katy Perry Wishes John Mayer's Dad a Happy Birthday: Photo

Thinking of the good times! Katy Perry left ex-boyfriend John Mayer a sweet note on his Instagram account — for his dad!

Mayer, 39, shared an adorable photo of himself and his dad, Richard Mayer, celebrating his 90th birthday at a restaurant.

"Happy 90th Birthday, Dad!" the singer wrote on Wednesday, October 11. "Leave doting comments about my dad below. He'll scroll through it. Also please stop this train. Thank you."

"Stop this train," of course, is a nod to his 2006 hit of the same name. In the song, the star says that he "had a talk with my old man" about getting older. "He said, 'Turn sixty-eight / You'll renegotiate / Don't stop this train / Don't for a minute change the place you're in / And don't think I couldn't ever understand / I tried my hand / John, honestly, we'll never stop this train,'" he sings.

Perry, 32, reacted to the sweet post in the comments section. "Looking fantastic as ever!" she wrote. "Happy birthday friend."

Perry and the "Gravity" singer split for good last year after dating on and off for three years. Mayer, who collaborated with her on 2013's "Who You Love," previously said that his new music is inspired mainly by her.

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