(CBS News) Jackson Rathbone and his girlfriend Sheila Hafsadi welcomed a baby boy on Thursday.
The couple named their son Monroe Jackson Rathbone VI.
Jackson tweeted, "I couldn't be happier to have such a beautiful, healthy baby boy."
The 27-year-old "Twilight" star met Hafsadi, a dancer, while on tour with his band 100 Monkeys.
"One of the greatest things I could expect to be in life is a father," the actor told Us Weekly in February. "I'm very excited."
Rathbone will appear in "The Twilight Saga: Breaking Dawn - Part 2," which hits theaters Nov. 16.