The 13th Annual Chrysalis Butterfly Ball

Congratulations are in order for Tom Arnold and Ashley Groussman.

The Sin City Saints actor, 56, and wife are expecting their second child – a daughter – he announced via Twitter.

The True Lies star captioned a cute shot of their 2-year-old son Jax holding an ultrasound image.

“Jax is very excited, but also a bit confused with the happy news he will have a little sister this fall. #grateful” Arnold announced.

The soon-to-be father-of-two has been open about the couple’s struggle to conceive.

“One day at the hospital I saw a sign asking for sperm donors and it paid $35. I was psyched because, unlike blood, I believed I could donate this stuff three times a day,” he told PEOPLE in 2013.

He added: “Fortunately, they give you a test first and the doctor informed me that I didn’t have many ‘swimmers.’ ”

After three failed marriages, Arnold wed Groussman in 2009 — and it sounds like fatherhood has been perfectly timed.

“I’ve worked diligently to become a father for 23 years,” he shared. “Twenty-one cycles of in-vitro with four different women, but the moment Jax was born I realized that this was exactly the way it was meant to be. I was ready because I was healthy and had the perfect partner.”

He added: “I’ve tried with other people, but since there is a God we were unable to conceive. Now God said, ‘This is it!’ ”

Jax is very excited but also a bit confused with the happy news he will have a little sister this fall. #grateful pic.twitter.com/xdy4vqlZLz

— Tom Arnold (@TomArnold) June 8, 2015

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