Clay Walker.Photo: Courtesy Clay Walker

Clay Walker

“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.”

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Kevork Djansezian/Getty

LAS VEGAS - APRIL 18: Musician Clay Walker (R) and wife Jessica arrive for the 45th Annual Academy of Country Music Awards at the MGM Grand Garden Arena on April 18, 2010 in Las Vegas, Nevada. (Photo by Kevork Djansezian/Getty Images)

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.”

“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.”

source: people.com