Josh went on to add: "If Brody being born on the 6th isn’t a sign, I don’t know what is!!"
Ashley penned a message of her own and said: "Brody Des Gibson born 06.09.21 💙 The purest love we’ve ever known."
The photos they shared included a family snap at the hospital right after Brody was born, followed by an adorable shot of Josh cradling his son while still at the hospital.
The couple first announced they were expecting a child in March this year, by uploading a photo of them together holding a photo of a baby sonogram.
"Little Gibbo coming September 2021," the 37-year-old penned.
"Hawks fans will be very happy to know, that scans show a large left 👊🏾! #goldenfist," he concluded.
The post included a second photo that showed a close-up of the sonogram, surrounded by blue and white baby-themed cupcakes.
In a previous interview with TV Week, Josh couldn't help but gush over his unborn baby, and said that he couldn't wait to be a dad.
"There have been a lot of great things in my life, and some wonderful achievements, but none will come close to being a father and having a little man," he said.
The proud parents are obviously smitten with their newest family member, as well as their friends and families who shared messages of congratulations in the comments.