"Friday, June 26, 2020, Our family became complete ❤️," Kelly, 42, shared on Instagram Sunday, posting a photo of her and Matthew, 32, in the delivery room and she underwent a cesarean section.
In the heartwarming photo, the Detroit Lions player could be seen gently resting his head next to his wife.
The couple shares three daughters: 3-year-old twins Sawyer and Chandler, and 1-year-old Hunter.
Just a few weeks before the birth, Kelly shared a sweet selfie of her family cuddled up in bed with the caption, "Room for one more will be needed here soon. ❤️."
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The couple, who married in 2015, first announced they were expecting their fourth child in early March when Kelly shared a sweet photo of the family at Disneyland to reveal the exciting news.
“Got to enjoy one of the most magical places with my husband and 3 of our kiddos. Not pictured: our middle baby girl, Huntie,” she shared, before adding, “Baby Stafford #4 due this summer (no worries, well before training camp) ??.”
“We won’t know whether the Stafford kids will continue as a girl squad or if a little brother will enter the craziness until baby is here,” she said, revealing their decision to keep the sex of their baby a surprise. “Excited and exhausted! #staffordpartyof6 #madeindetroit#nomoresedans #staffordstrong.”
Kelly later shared a second photo to her Instagram Story, showing off her baby bump in a red figure-hugging dress, telling her fans that this would be her last pregnancy.
“And yes. We are done after this,” she captioned the photo. “Stafford party of 6 will stay a party of 6.
Kelly announced her pregnancy nearly one year after she underwent a 12-hour brain operation in April 2019 when doctors found a benign tumor resting on her cranial nerves.
On the one-year anniversary since the surgery, Kelly shared an emotional note on Instagram, writing about the "hardest year" of her life.
"One year ago today. I really can’t express what I’m feeling today. My feelings are all over the place," she began. "The scheduled 6 hours, turning into 8 hours, turning into 10 hours, and finally doctors closing me up at the 12 hour mark.. friends and family anxiously awaiting wondering what is going on."
"What was going on was my doctor was saving everything.. hitting some unexpected bumps along the way, but taking all the time and precautions needed. Dr. Thompson is a truly special man and I’m incredibly thankful God led me to him and his team," she added. "I’m thankful for my family and friends who rallied behind me and encouraged me through the extremely tough times, which happened more than people knew in the past year."
She then gave Matthew a special shout-out, writing "You are the only reason I got through this past year. So many ups and downs and you were such a strong foundation to lean on.. even in some of your most difficult times. Thank you for getting me through."
"And my kids.. you’ll never know how much I pushed myself for you. How much I wanted to get back to the mommy you three deserved," Kelly continued. "You and your daddy are the major reason my recovery went the way it did. I love y’all so much."
"The hardest year of my life so far has passed. I am looking forward to the years to come knowing that they might bring new challenges, but ready for those challenges because not only do I now know how strong I am, but more so how much stronger I am with my husband and kids by my side," she ended her note. "Thank you. And I thank God this year is over and I live to see another!"