The Parks and Recreation actor, 48, is currently skiing in Aspen, Colorado, with his sons Matthew, 19, and Johnowen, 17. Rob has shared several pictures of their "father and son adventures" via Instagram, including one of him and Matthew "getting 30,000 vertical in one day."
"Let's make 2013 a Mount Rushmore of love, health, laughs and achievement!" the actor tweeted Dec. 31.
Patrick Schwarzenegger, a longtime family friend, is also on the trip with the Lowes and several other pals. "Excited for nice week of skiing," the college student, philanthropist and model tweeted Jan. 1.
"Time to ski hard and party even harder," Matthew tweeted. "The boys are killing it in Aspen.
(Matthew is currently enrolled at Duke University in Durham, North Carolina, while, while Schwarzenegger, 19, attends the University of Southern California in L.A.)
While promoting his memoir, Stories I Only Tell My Friends, on The Oprah Winfrey Show in 2011, Rob opened up about his two sons. "The main thing you need to know about Johnowen is he is very, very social and very, very smart," the Outsiders star said. "Matthew is one of the great water men that I know. He's a surfer, a great water polo player. I think he's half fish. Also, I'm really blessed that both boys are very, very bright."