SARASOTA, Fla. (WFLA) – Students and staff at Sarasota High School are mourning the loss of a beloved teacher who died of coronavirus this week.

Robert Shackelford, a longtime social studies teacher at Sarasota High School died Wednesday from complications of COVID-19, the school’s principal, David Jones, said in an email to staff.

“It is with a very heavy heart that I write you. Our beloved teacher, Robert Shackelford, lost his life today to COVID-19,” Jones wrote. “Our sorrow is abiding, and perhaps one of the few consolations we have is the knowledge that we were privileged to know and work with Robert over the years. During that time, we came to know him as a person of intelligence, integrity, and incredible conscientiousness, whose life and career were indeed an inspiration to us all.”

“Our hearts and our prayers are with his family and with our SHS family at this most difficult of times,” Jones continued.

Shackelford’s family tells 8 On Your Side, the 61-year-old was strong, healthy and did not have any underlying health conditions before contracting the virus.

“We thought if anybody is going to beat this, Rob is going to beat this,” said Shackelford’s sister Jo Lumpkin.

Lumpkin says the virus proved its power once infecting her brother.

“It got to the point where he’s sitting in his condo and he calls my mother and says, ‘mom, I can’t breathe’,” said Lumpkin. “This thing got into his lungs and it ravaged them. The pulmonologist told us he had so many holes in his lungs, his lungs were so brittle that they were irreparably damaged from this invisible virus,” she continued.

Shackelford’s family is urging people of all ages to take COVID-19 seriously.

“It is not a joke and every person needs to be wearing a mask to protect the people they come into contact with — old, young, healthy, not healthy, it doesn’t matter because it affects everyone so differently,” said Lumpkin. “It is just a cautionary tale for those people who just believe that this is just something like the flu. It absolutely is not. It just isn’t and unfortunately we had to lose a loved one,” she continued.

Shackelford is being remembered by his love for history, patriotism, education, and his family. “He loved his brother Steve and family was just very important to him,” said Lumpkin.

Longtime friend and colleague Gina Barresi tells 8 On Your Side Shackelford was one of a kind.

“Despite his large stature, being a football coach, and his booming commanding voice and presence… he was probably one of the most tender men that I have ever known,” said Barresi.

“His brother who has cerebral palsy created an empathy in him that most people dont have. He had a very very soft spot for people with disabilities. My daughter has down syndrome and he just absolutely adored her and she did him,” said Shackelford’s close colleague.

Barresi says Shackelford would spend his lunch in the classroom with kids with intellectual disabilities. “He would high five them all and he would say ‘how are we all doing today kids’ and they would just run to him and he would give them these big bear hugs. That is what made him special; how many men do you know like that?”

Shackelford was named Sarasota’ High School’s teacher of the year in 2015. Former students are drowning social media with tribute posts in memory of the man many knew as “Shack” or “Coach Shack”.

News of his death comes after Sarasota reported 135 new cases Wednesday and one new death. The county has tallied a total of 4,567 cases and 109 deaths.

Statewide, 379,619 people have tested positive for the virus and 5,345 people have died, according to Wednesday’s report.