Dan Reynolds is a dad — for the fourth time.
Alongside a photo of the newborn baby boy, Reynolds, 32, also addressed the second anniversary of the 2017 Las Vegas shooting, the deadliest mass shooting in modern U.S. history, and shared the sweet way the couple chose to honor the victims.
“The name Valentine means ‘strong.’ As today marks the 2nd anniversary of our most tragic day in Vegas, it now also represents the day that we celebrate the birth of new life. We are truly feeling #vegasstrong today,” wrote Reynolds, a Las Vegas, Nevada, native.
Volkman announced her son’s birth on her own Instagram, sharing a photo of a shirtless Reynolds and Valentine doing skin-to-skin as the newborn slept. “Valentine Reynolds my heart just exploded for the 4th time,” she wrote.
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The couple — already parents to twin daughters Gia James and Coco Rae, 2, and daughter Arrow Eve, 7 — surprised fans when they revealed in April that they were expecting again, only two months after their reconciliation.
“I’ve been on the road for a decade now. I’m looking to take a little bit of time off. I have three little girls, and well, I have one on the way,” Reynolds said at the time. “I actually haven’t told anybody that. There it is. The news is out. We just found out we’re having a boy [in] October.”
“My wife and I have gotten back together,” the singer said. “We went through a separation for a little while, so [I’m clearing] that up. So I have to be public to let people know we are back together.”
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Although the couple were elated to be growing their family, there was one member of the Reynolds bunch who was less than thrilled to find out the baby on the way was a boy.
“Arrow was pretty upset,” the “Thunder” singer told PEOPLE in May. “I told her she was having a brother and you know what she said to me? I can’t tell you all of this story because it puts someone on blast but she said, ‘I really don’t want to have a brother if it’s like … and then she said a boy that she knows, but if it’s like River — which is [my bandmate Daniel Wayne Sermon’s] son — then I’m okay with it.’ “
He added, “She was almost in tears about it. I said, ‘Our son will be like River, I promise.’ I really hope that’s true!”