Chris Klein is officially a dad!
The American Pie star and his wife, Laina Rose, welcomed their first child, announcing the news via social media on Wednesday.
WATCH: 9 Celebrity Babies Due in 2016
Frederick Easton Klein was born in Austin, Texas, last Saturday. A source confirmed to ET that Frederick arrived two weeks late, but mom and baby are doing well.
Judging by the adorable photo Laina posted, Frederick's personality is already shining through!
"So excited to announced our precious baby boy, Frederick Easton Klein was born on 7/23/16," Laina wrote with a precious snap of the newborn pumping his fists in the air. "This little Champ has already mastered his warrior pose and is doing great. Our hearts are bursting with love and joy?#staylittleforever #wakingupklein#chrisklein #partyofthree."
Chris, who is "madly in love" with his son (and adjusting to life with less sleep), tweeted a photo of the newborn on Wednesday, along with a sweet message to his wife. "So incredibly blessed and forever grateful for my amazing wife & our healthy baby boy," the 37-year-old actor lovingly wrote. "Laina delivered me a miracle."
Prior to the little bundle of joy's arrival, Laina wasn't shy about documenting her pregnancy journey with fans. On Saturday, she took to Instagram to share a pic of her and Chris' dog, Chief, taking a nap.
"Getting in some quiet moments before the little one arrives," she captioned it, using the hashtags "#saturdaynaps," "#40+weeks," "#40weeks," and "#countingdowntobabyklein."
Laina also gave her followers a peek of her burgeoning belly at 39 weeks over the "hot" Fourth of July weekend, wearing a body-hugging American flag-printed dress while posing next to her pal, Stephanie Collins.
Chris adorably announced that Laina was pregnant on his 37th birthday in March. "My beautiful wife Laina and I are expecting our first child," he tweeted. "23 weeks along. Gratefully blessed on my 37th B-Day."
The new parents said "I do" last August in a small intimate ceremony at the Rainbow Ranch in Montana. The two met at a mutual friend's wedding and dated for four years before tying the knot.
Congrats to the happy couple!
WATCH: Russell Brand Is Going to Be a Dad -- See His Funny Announcement!
In more baby news, Russell Brand is also preparing to be a first-time father. After rumors began swirling in May that his girlfriend, Laura Gallacher, was pregnant, the 41-year-old comedian finally confirmed the news via Instagram on Friday.
"Right then. My Mum bought me this," the Get Him to the Greek star captioned a photo of himself reading Dean Beaumont's "The Expectant Dad's Handbook." Hear more in the video below.