Pennsylvania couple Sean Stevenson and Christine Swidorsky got married this past Saturday.
Their 2-year-old son, Logan, served as best man.
The toddler, who had been suffering from acute myeloid leukaemia and other serious complications for most of his young life, was carried down the aisle by his mother in a dapper pinstripe suit. Knowing their son had just weeks to live, his parents moved up their wedding date so he could be there.
"With Logan being sick all the time, we just held off," Stevenson told CBS News. "We always knew that he was going to get better."
"Under the circumstances of what the doctors told us, we just decided to go ahead and do it while he was still with us."
"This is our dream come true, all our family together, and we're all together celebrating. A celebration of my son's life and a celebration of our marriage," the bride said on their wedding day.
Swidorsky's 13-year-old daughter, Isabella Johns, was a bridesmaid. The couple's one-year-old daughter, Savannah, was the flower girl.
Today, a family spokesperson confirmed little Logan passed away:
"Logan passed away at 8:18 yesterday evening, surrounded by his family and loved ones. He was very comfortable."
"He is with angels and he's in no more pain," the boy's mother wrote on Facebook, adding, "My son took his last breath in my arms."
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After news outlets shared Logan's story, support poured in from around the country.
"I am so thankful his story was out there, and we got to share his story with the world," Swidorsky told TODAY on Monday. "We just want everyone to know who Logan is. His legacy is going to live on."