Carrie Underwood marked a special occasion on Thursday -- her youngest son, Jacob, turned two.
The country singer explained in a heartfelt message to fans why her son's birthday means so much to her.
"Jacob, we longed for you. We prayed for you. We walked a long, hard road in order to one day hold you," Underwood shared alongside a photo of a newborn Jacob. "Today you are two."
The 37-year-old mother of two described little Jacob as "silly and strong" who loves to "play and sing and follow your big brother around."
"You are loved. You are cherished. You are an incredible blessing from God," she added. "Happy birthday, sweet boy!"
The American Idol winner, who shares Jacob and son Isaiah, 5, with husband Mike Fisher, previously revealed that she suffered three miscarriages over the course of two years before becoming pregnant with her youngest child. She also revealed that she had a scare that she was losing that pregnancy, too.
During a 2018 interview on CBS' Sunday Morning, the singer spoke openly about the grief she felt when she thought she was losing Jacob.
"I was just sobbing," Underwood said at the time, explaining that she was praying constantly when she thought she was having another miscarriage. "I was like, 'Why on Earth do I keep getting pregnant if I can't have a kid? Like, what is this? Shut the door. Like, do something. Either shut the door or let me have a kid.'"
"That was like a Saturday -- and the Monday I went to the doctor to, like, confirm, another miscarriage. And they told me everything was great," the seven-time Grammy Award winner recalled. "I was like, 'You heard me.' Not that He hasn't in the past. But maybe, I don't know, He heard me."