The singer’s wife, Ari Whibley, shared the news Friday on social media.

“Deryck and I were suppose to be in Chicago right now, celebrating our eight year wedding anniversary but the universe had a different plan for us,” she wrote in an Instagram post that featured pictures of the musician receiving medical care. “We spent the entire night in the ER and will now be spending the next few days here in the hospital as he fights through pneumonia.”

She explained that, though Whibley is only 43, the illness has the potential to be grave.

“The scariest part is that there is a lot of strain on his heart and they are telling us that there is a possibility of heart failure,” she said.

Representatives for Sum 41 did not immediately respond to The Times’ request for comment.

Whibley has had several health issues over the years. He has repeatedly injured his back, which caused him to miss many performances. In 2010, the “In Too Deep” singer was hospitalized after he was attacked by three people at a bar in Japan. He revealed in 2014 that he was hospitalized for severe liver and kidney damage due to alcoholism.

“This is obviously not our first time in a situation like this but it brings back a lot of really difficult memories seeing him back in a hospital bed connected to wires and IVs,” Ari Whibley’s statement continued.

“I know how strong he is because I have witnessed what he has been able to overcome but that doesn’t make it any easier to see. I’ll do my best to keep everyone updated but if you could keep him in your heart over the next few days, we could really use it.”