The brothers both welcomed their babies at 6:53 p.m. in two different hospitals.
Matt Thayer, 31, and his wife Brooke Thayer were expecting their first baby, a little girl, March 25. Their doctor changed the due date to the 20th after noting the progression.
Matt's brother Steve Thayer, 34, and his wife Fawn planned to welcome their third child, a boy, a few days later on the 23rd.
Both brothers said they've always been competitive, and Matt thought it would be great if both babies were born the same day, but no one knew just how close the times would be.
"Me and my brother we've had the typical brother relationship, rivalry," Matt said. "I was prior Army, he was prior Navy so we constantly had that little battle going."
"We're definitely sibling rivals," Steve said with a laugh.
Brooke went into labor at Moore Regional Hospital in Pinehurst around 8 a.m. on March 20. Fawn started experiencing contractions and went to Duke Children's Hospital in Durham around 4 p.m. that afternoon.
Fawn said she thought Brooke would've definitely had her baby first since she had been in labor since that morning, and never imagined her labor process would be so quick.
Matt and Brooke welcomed their new daughter Cassidy at the same time Steve and Fawn welcomed their son Benjamin.
It wasn't until both the brothers started texting photos to their dad that everyone figured out what was going on.
"Right after we sent him the pictures of our daughter," Matt said. "He got another picture and said 'oh my God, it's a boy,' so he realized 'hey they were pretty close right there.'"
"We knew it was going to be close because they went into labor on the same day, but we found it hard to believe it was the same minute," Steve said. "The more we talked to the nurses, the realization sunk in that we both had our babies at the same time it was really special."
"We thought it was really cool that this is something the two cousins can share for the rest of their lives," he added.
"It's really surreal," Matt said. "It's really interesting when you really think about it. It's just unbelievable."
The baby cousins met for the first time March 26, the Saturday before Easter.
Their families said they already have plans to celebrate their shared birthday together, having one big party for both, in the years to come.
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