In a side-by-side photo, a grieving Maryland mother revealed the profound heartbreak of losing a child to cancer.

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In a collage, a photo on the left shows Nolan, 4, curled up on a bathroom rug, waiting for his mother to get out of the shower. On the right, the space where Nolan lay is empty.

Last week, Ruth Scully wrote about her son's final days and the pain of his loss in an emotional Facebook post two months after his death. Nolan died on Feb. 4 of this year after being treated for rhabdomyosarcoma, a rare and aggressive childhood cancer that attacks soft tissue.

“My son was terrified to leave my side, even as I showered,” Scully wrote. “Now I’m the one terrified to shower. With nothing but an empty shower rug now where once a beautiful perfect little boy laid waiting for his Mommy.”

According to The Enterprise, Nolan was diagnosed with cancer at age 3 and underwent numerous treatments over a year and a half. His family chronicled his ups and downs on a Facebook page called NolanStrong, which attracted more than 100,000 likes and drew a community of supporters from as far away as Australia.

Nolan dreamed of being a policeman when he grew up, and his Facebook page was full of visits from first responders. He was even named an honorary police officer by the Philadelphia Police commissioner before his death.

In her emotional post, Scully detailed her son's last minutes, including the moment he reminded his family that he wanted to be remembered as a policeman.

“All Nolan ever wanted to do was to serve and protect others, he did just that all the way up to his last breath and continues to do so every day,” Scully wrote. “At 11:54 pm, Sgt. Rollin Nolan Scully passed away as I was singing, ‘You are My Sunshine’ in his ear.”

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