Jensen Ackles and his longtime girlfriend Danneel Harris are engaged, her rep confirms exclusively to JustJared.com.

The 31-year-old Supernatural actor and 30-year-old One Tree Hill actress have been dating for about three years but have been friends for nearly a decade. The couple, who are longtime members of the WB/CW family, co-starred in the 2007 romantic comedy Ten Inch Hero.

Danneel showed off her beautiful engagement ring on Saturday at the Breeders’ Cup in Los Angeles.

Congrats to the happy couple!

Yay!!! I’m so happy for them! My favorite celeb couple finally getting engaged!