Clay Walker Reveals Wife Had Miscarriage with Baby at 20 Weeks (Exclusive)

The country singer announced just weeks ago that he and wife Jessica were expecting their sixth baby together, a daughter

Just weeks after Clay Walker announced that he and his wife Jessica were expecting their sixth baby, the country singer is revealing that she had a miscarriage at 20 weeks pregnant.

"The whole family had been waiting for the baby and it was really, just a huge blow," the country singer, 53, who has four sons, Christiaan, 2, Ezra, 5, Elijah, 10, and William, 14, and one daughter, Mary-Elizabeth, 13, with Jessica. He is also dad to two adult daughters Skylor and MaClay, from a previous relationship.

"We had her room ready, her clothes bought — everything, and her name, Eleanora Lindsey," the multi-platinum artist tells PEOPLE from his home in Texas. "So, it was a nightmare and still is for my wife. We were at 20 weeks, and we'd already made it through the toughest part. We've had five successful full-term pregnancies and five beautiful children. It's tough."

Until recently, the baby had shown no signs of distress. "We had the 13-week checkup and we saw her doing acrobatics," says Walker. "We were laughing so hard because she was so active. And just everything was so perfect."

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While the couple has relied on their faith to get through this challenging time, the country star — known for hits such as "She Won't Be Lonely Long" and "If I Could Make a Living" —knows it will take a long time to recover from such a devastating loss.

"We've got a great friend group that's been there for us, you know, a lot of prayer," says Walker, who's been married to Jessica, 40, for 15 years. "And we've had a lot of prayer internally in our home. But still, you know, I could talk all day about this."

"I just don't know how moms make it through the rest of their lives with that kind of pain," he says. "It's just so, so deep. And you know, as a husband and a father, not being able to do anything about it, not being able to protect my wife's feelings or the baby, sucks."

"It felt like we got run over by a train and just watching my wife suffer through that," adds the singer. "I feel for all the women out there who have been through a miscarriage, just because you're losing a child."

"When I was diagnosed with multiple sclerosis, I never asked God 'why,' " says Walker, who was diagnosed with the disease in 1996. "But you know, if I make it to heaven, [asking why this had to happen to us] is going to be my first question. There's no understanding this for me, and especially for a mom that's the greatest mom. She just tries to be the best mom and wife that she can be. It's unfair."