The Harry Potter actor -- who played Hogwarts student Seamus Finnigan in the celebrated film franchise -- announced the exciting news to Instagram on Sunday.
"Yesterday 2/1/21 my life changed forever. Shannon delivered our beautiful little boy ‘Cooper Michael Murray’ weighing 6lbs 10oz," Murray wrote. "Both are doing amazing now after a very long labour and a scary few minutes at the end."
The actor shared the announcement alongside a snapshot showing a cupcake with a blue footprint in the foreground, and his new baby boy sleeping peacefully in a hospital bassinet in the background.
"It still hasn’t sunk in just yet that we have our very own little boy," the new father continued. "I can’t wait to make the most amazing memories with Shannon and Cooper as we begin our little family."
Murray praised his girlfriend, writing that he is "so amazed by Shannon and she is now my Hero."
"I’m so proud of her for everything she has gone through," he concluded. "I can’t wait to have you both home. It’s so hard having to leave you both. I will love you both forever until my last breathe ❤️🍼👶🏻."
Murray first announced that he and McCaffrey were gearing up to become parents back in July, sharing a heartwarming snapshot of a sonogram and a cute baby onesie to Instagram.
"Baby Murray - 14th of January 2021," Murray captioned the cute pic, revealing his girlfriend's expected due date -- meaning she ultimately delivered their baby boy two weeks earlier than expected.
After being inundated with congratulations and well-wishes on his pregnancy announcement, Murray responded in the comments to his post, sharing, "We're both so happy, excited and nervous and can not wait until he/she are in our arms."
Check out the video below for more on the latest celebrity baby news.