Ryan Phillippe and his 17-year-old daughter, Ava, look so alike, people often think they're siblings!

"My daughter gets embarrassed sometimes by the fact that I do look so young and I get mistaken for her brother sometimes," Ryan, 42, admitted during a recent appearance on The Late Late Show with James Corden.

"[It] repulses her! Like, absolutely repulses her that anyone could mistake me for her brother," the actor added.

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Ryan and his ex-wife, Reese Witherspoon — who were married from 1999 until 2007 — welcomed Ava in September 1999 and their son, Deacon, 13, in October 2003. The Cruel Intentions star is also a dad to a five-year-old daughter, Kai, from a previous relationship with actress Alexis Knapp.

Click through the gallery below to see Reese and Ryan’s kids through the years!