Watch Keith Urban Serenade Gravely Ill Fan in Ohio

Country superstar Keith Urban may have performed for thousands in Toledo, Ohio on Thursday night, [...]

Country superstar Keith Urban may have performed for thousands in Toledo, Ohio on Thursday night, but his shining moment came when he surprised a gravely ill fan with an impromptu concert after the help from her family, friends and a viral campaign.

Urban took the time from his Graffiti U Tour to serenade 25-year-old Marissa English from her bedside at Mercy Health St. Vincent Hospital prior to his concert.

According to CBS News affiliate, WTOL, it took a minute or two for English to register that Urban was there for her, where he spent a total of 45 minutes and belted out "Blue Aint' Your Color."

English, whose condition has been rapidly deteriorating, suffers from several health conditions, including cerebral palsy, severe scoliosis and an inoperable cyst on her brain. The mega fan's nurses appealed to Urban via social media in hopes she could get her wish to see Urban in concert.

"We knew how important it was to Marissa to be at that concert [on Thursday] and since she wasn't able to we were hoping to try and find some way to have Keith make a connection with her," nurse Jan Cassity told WTOL.

English's mother, Marlise Matthews said the whole experience meant the world to her daughter and their family.

"He sat with her and held her hand and talked to her and sang with her," Matthews said. "It was ... it was priceless. I mean, a dream come true."

English has reportedly been a fan her whole life and held onto hope as her health declined that she would one day meet her idol. Her mother goes on to add that when her daughter met him, the physical effects the visit had on her surprised everyone.

"The overall calming effect it had on her, too," Matthews said. "She's been having a lot of difficult days, but she relaxed. Her heart rate actually came down, which surprises me because I thought it would go up, but she was just enjoying the moment."

Matthews went on to acknowledge how "busy" Urban has been with his tour, but that she was eternally grateful he "took the time to come and see his biggest fan."

Shortly after visiting with English, Urban dedicated his show to her Thursday evening, telling concert-goers how he met a "beautiful girl named Marissa" who he truly believes is "his biggest fan."

Photo credit: Facebook / Garrett English / @HannahsHappyBundles