The model, who married Whibley in 2015, revealed that the couple were supposed to be in Chicago celebrating their eight-year wedding anniversary but that "the universe had a different plan."
"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 wrote. "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."
Alongside her post, Ariana shared a snapshot of her holding onto Whibley's hand, which featured a pulse oximeter on his index finger as well as an image of the musician sitting in a stretcher in front of an ambulance.
Ariana concluded, "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."
Whibley was previously hospitalized after his liver and kidneys collapsed due to longtime alcohol abuse in 2014. He recovered there for a month, during which he was placed in a medically induced coma for a week to deal with withdrawal symptoms.
"I finally realized I can't drink anymore. If I have one drink the docs say I will die," he said of the health scare in a post on his since-deleted website. "I'm not preaching or anything, but just always drink responsibly. I didn't, and look where that got me."
The following year, the Canadian rocker, who is a father to two children, told Vice that he was "feeling better than I've ever felt" thanks to his ongoing sobriety journey. "I'm healthier. I'm in the best shape of my life," he said. "I'm more productive. Well, I was always really productive, but I was just good at being a functional alcoholic."
Burak Cingi/Redferns Deryck Whibley of Sum 41
In May, Whibley — alongside his Sum 41 bandmates Dave Baksh, Jason McCaslin, Tom Thacker, and Frank Zummo — announced in a statement that they were going their separate ways following the release of their final album, Heaven :x: Hell, and embarking on one last tour together.
"Being in Sum 41 since 1996 brought us some of the best moments of our lives," the statement read. "We are forever grateful to our fans both old and new, who have supported us in every way. It is hard to articulate the love and respect we have for all of you, and we wanted you to hear this from us first."
The group continued, "We will still be finishing all of our current tour dates this year, and we're looking forward to releasing our final album, Heaven :x: Hell, along with a final worldwide headlining tour to celebrate. Details will be announced as soon as we have them. For now, we look forward to seeing all of you skumfuks on the road and are excited for what the future will bring for each of us."
Known for hits like "Fat Lip" and "In Too Deep," the band is still currently scheduled to perform their final, sold-out show in Nanterre, France, on Sept. 23.
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