Imagine Dragons Singer Dan Reynolds Expecting Baby Boy With Wife 1 Year After Separation

Imagine Dragons frontman, Dan Reynolds is expecting his fourth child with wife, Aja Volkman in a [...]

Imagine Dragons frontman, Dan Reynolds is expecting his fourth child with wife, Aja Volkman in a reveal shared Wednesday.

According to Us Weekly, Reynolds exclusively told the publication that despite he and Volkman separating last April and reconciling this past January, they are now welcoming a baby boy together.

"We have a boy on the way," Reynolds said. "Three girls and a boy on the way, due in October."

He adds that his wife is "feeling upset" with him because he was a "really big baby" and is afraid that will repeat with this birth.

"I was over nine pounds … and she's showing much more than she was with the girls," the 31-year-old said. "Because of that, the musician joked that he has been telling her to 'eat those potatoes [and] drink a protein shake' for an even bigger baby.

Reynolds and Volkman of the band Nico Vega, tied the knot in 2011 and began growing their family just a year later. Welcoming their first child, daughter Arrow, 6, in 2012, the two welcomed fraternal twin daughters five years later, Gia and Coco, 2.

The "Radioactive" adds that he and his wife are "done, done, done" having children and that they are now "complete."

It is an incredible change in relationship dynamics for Reynolds and Volkman who revealed last April that the two were splitting up after seven years together.

"After 7 beautiful years together, Aja and I's marriage has come to an end. Our children continue to be the most important thing in our lives, [and] we will continue to co-parent them with all our love," he shared to social media last April. "I ask that you please respect our privacy at this time as we work through this as a family."

However, earlier this January, Volkman revealed she and Reynolds were working on "rebuilding" in a post shared to social media in January.

"I'm so proud of you [Dan Reynolds] I'm proud of your humility and ability to still show up as the basketball coaching baby loving Dad that you are," Volkman penned in an emotional message. "I know that it's been a crazy road. It's killed us both in so many moments," Volkman continued. "Last year we killed each other and now we are rebuilding. You can become your worst self in the eye of a giant storm. You almost have to. It's rite of passage. It's the only road to a better existence. A more mature sense of self."

Reynolds previously told PEOPLE that he was working through the motions of their relationship and always made sure his kids were his top priority.

"I have three little girls and this year for my family has been kind of a difficult year for personal and emotional reasons," Reynolds said at the time. "And just going through that and watching the effect on my girls has been very hard for me."

Amid the happy news of a new baby on the way with wife Volkman, Reynolds launched Monster Pain the AS on Wednesday, April 3 — a national campaign to raise awareness of a disease he has been battling for more than a decade now called ankylosing spondylitis (AS). The chronic inflammatory condition of the joints can lead to extreme pain and in worst cases, spinal fusion.

Reynolds is one of the estimated 2.7 million people in the U.S. thought to have AS and is using his voice in hopes of encouraging others living with persistent, unexplained back pain to seek diagnosis and care.

The singer and songwriter opened up to PEOPLE about his battle in 2016, revealing how debilitating the disease was on his overall health and well-being.

"There was probably six months of my life where I could hardly do anything — I couldn't lift things, and [my wife] was just patient through all of it," said Reynolds, who underwent treatment and is now in remission.

Reynolds added that his daughter Arrow and his twins were huge motivators in keeping his health the best it can possibly be.

"My daughter [Arrow] is just the light of the world," he said. "She's my everything and the thought of not being able to pick her up is just the worst thought that a father could ever have."

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