Rob Lowe Works Out With Really Hot Son John: Sweaty, Dreamy Photo!

Generational #Fitness with @johnnylowe #Essential #Results #ForeverYoung #Profile4Men

A photo posted by Rob Lowe (@robloweofficial) on Jun 23, 2015 at 2:19pm PDT

Those genes, though! Rob Lowe broke a sweat while working out with his dreamy and adorable (and did we say hot!?) son John on Tuesday, June 23.

"Generational #Fitness with @johnnylowe," the ageless star, 51, captioned an Instagram pic of the two. "#Essential #Results #ForeverYoung #Profile4Men."

In the selfie, the Parks and Recreation hunk went shirtless and wore a white towel around his neck. John, 20, (with the same piercing blue eyes!) kept his on while listening to music.

The West Wing alum and his wife of 24 years, Sheryl Berkoff, are also parents to 22-year-old son Matthew. Last year, Lowe opened up about balancing fatherhood with fame. "I'll never really know what it's been like for [John and Matthew] out in the world and having people talk about me. Good or bad," he told Maria Shriver. "It's not ever something they ever want to talk about with me and don't."

Rob Lowe with family
Rob Lowe with wife Sheryl Lowe and children Matthew Lowe and John Lowe on September 18, 2011 in Los Angeles, California. John Sciulli/WireImage.com

"That's either the really, really good news. Or the really, really bad news," he continued. "Either way, they don't do it. I think one of the things I did early on was — Sheryl and I moved out of Los Angeles."

Lowe overcame addictions as a young Brat Packer. He quit drinking in 1990 after rehab, and has now been sober for 25 years.

"We don't live in a community where everyone is quite as fixated on entertainment," he added to Shriver. "And I think that helped them have a sense of me that isn't just exclusively that I'm an actor."

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