Although the "Blue" country singer, 35, is a stepmom to current husband Eddie Cibrian's two sons Mason, 14, and Jake, 11, Rimes hasn't given birth to a child of her own and Sheremet's news has hit her hard, a source told Radar.
"LeAnn and Eddie have been trying for years, so Dean’s announcement must have been a bitter pill for her to swallow," a friend of the couple said.
Earlier this month, dancer, chef, and cookbook author Sheremet, 37, announced that he and filmmaker fiancée Black were going to have a baby this summer.
"It has been a lifelong dream of mine to be a father, and I cannot wait to nurture a family full of love and adventure," he said.
In a blog post, Sheremet elaborated upon learning the news that Black was pregnant, "In this moment, I knew why I was here. My purpose on this planet. Why she and I met and fell in love. And why every thing I’d ever questioned, every pain, each rejection, failure and fortune had to happen for this to be possible."
The two had gotten engaged in March.
Rimes and Sheremet split in 2009 as the country star cheated on her husband with also-married actor Eddie Cibrian, whom she met while doing the TV movie "Northern Lights." Sheremet later said he was completely blindsided by Rimes' infidelity.
Rimes and Cibrian shed their respective spouses and married each other in April 2011.
According to Rimes' pal, she and Cibiran have had trouble conceiving "the old-fashioned way" and are now considering adoption or surrogacy.
"LeAnn hasn't given up hope, but this is just another painful reminder that she hasn't been blessed with a baby of her own," the insider said.
The singer has sighed, "It took my mom 12 years to have me. I hope I don't have that issue."
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