Mark Ballas and Kacper SobieskiBC Jean are reflecting on a heartbreaking time in their lives.

The Dancing With the Stars alum and songwriter, who are currently expecting a baby together, detailed their experience with a miscarriage in their new song "Rainbow."

"We lost a baby last year," they wrote on their band Alexander Jean's Instagram page Oct. 5, "just when we thought we were in a good place to tell friends + family, we received the heavy news that our little one wasn't going to make it. We've been through hard times in our lives, but this was a different kind of sadness."

Their song serves as a tribute for anyone that experienced loss.

"We hope it brings whoever listens some kind of peace," they continued, "and reminds you that a rainbow isn't far behind."

In the three-minute single, Jean sings, "Give me some good news / Something to look forward to / Nothing I could do would put the life back into you."

In June, the couple—who tied the knot in 2016—announced they were overjoyed to learn they are expecting a baby.

"Lately we've been...," the couple captioned a joint Instagram post June 26, "making new music, making birthday wishes, went to Disneyland, made more music stuff, turned off our phones and went to the beach, car rides with our best mate, Boba tea, made more music."

Their caption continued, "Also, we've been making.... a tiny human."

Two months after their announcement, the ballroom pro shared a sweet glimpse into his wife's pregnancy journey.

"Big jumps + little hands," he captioned an August Instagram video of the couple at a doctor's visit. "Seeing our baby move for the first time was an experience & a moment I'll never forget, I can't wait to meet you little one I'm all in my feels, now that it's getting real."

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