The couple share Nick, 19, and Leila, 23, together and also daughter, Courtney, 34, from his previous marriage to Alice Bell.
However, Al and Deborah had trouble conceiving and at one point thought it would never happen.
WATCH: Al Roker celebrates wonderful news about son Nick
The much-loved Today show weatherman opened up to Guidepost.org back in 2003 and detailed their emotional journey to their miracle baby.
He explained how after a year of marriage, they decided to have a baby together. They were already raising Courtney, but wanted to add to their brood.
"But try as we might, for more than a year, she didn't conceive," Al wrote in his poignant piece for the outlet. The doctors told them that it was taking longer than anticipated and suggested they both get tested to make sure nothing was wrong.
Al and Deborah are proud parents to their three children
"The problem was me," Al said. "I was more relieved than anything else. Now we knew for sure what the trouble was. Besides, as a weatherman I'm used to a certain amount of failure."
While they were advised to seek help from a fertility clinic, Al said that he and Deborah wanted to keep trying for a while - but still, nothing happened.
"Every time I saw one of those commercials showing a happy couple with a positive on their home pregnancy test, I wanted to throw something at the TV," Al wrote.
Al and Deborah struggled to conceive Leila - pictured right
Deborah had remained hopeful and said: "If it's meant to be, then God will make it happen."
And it did, but only two months into the pregnancy, they were told the baby wasn't developing properly and she sadly miscarried.
Al and Deborah were desperate to bring a baby into the world and once they were able to deal with the pain of their miscarriage, they decided to try IVF.
Discovering it had worked was a momentous moment, as was hearing her heartbeat after the first trepidatious trimester.
Al and Deborah conceived after IVF
"Science may have helped us on our path to pregnancy, but it couldn't get us all the way to the end," Al added. "The only thing that could do that was the power and grace of God. He'd been with us on this journey every step of the way. This was his miracle; the beautiful, glorious, humbling mystery of life."
Al continued: "At 9:17 a.m. on Tuesday, November 17, 1998, I heard the most wonderful sound: the cries of our newborn daughter, Leila Ruth Roker.
He concluded: "My little girl wriggled in my arms and all at once I felt warmth surge through me. Love. For Courtney, for Leila and for Deborah. This was the answer to the mystery that had driven Deborah and me to want a child so much. Love without limits, just like God's love for all his children."
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