On 9 June, Howie Dittman and a group of others went down to the Pride celebrations in Pittsburgh, Pennsylvania, wearing t-shirts that said 'Free Dad Hugs' and 'Free Mom Hugs'.
Sharing what happened on Facebook, Dittman wrote: "We gave out hundreds of hugs. Hundreds. Some were super happy hugs."
Referring to the two photos attached to his post, which show him hugging two strangers, he added: "But others were like these two... and there were way too many like them."
Dittman explained that one man he hugged was kicked out of his family home at the age of 19, and that his parents haven't spoken to him since.
He continued: "He cried on my shoulder. Sobbed. Squeezed me with everything he had. I felt a tiny bit of that pain that he carries with him every minute of every day. He was abandoned because of who he loves."
Dittman said another woman had spotted him from across the street, and by the time she got to him, she had tears in her eyes.
"She stood in front of me and looked up at me, with a look of sadness and helplessness that I'll never forget," he said.
"She hugged me with everything she had. And I hugged her back. She held on for so long, melting into me, and thanked me endlessly.
"And I can't stop thinking about her. What she must be going thru with her family... the ones who are supposed to be there for her no matter what. Who does she go to when she needs advice on love, money or just life? Who does she share old memories with that only her parents would have been there for? What are her holidays like?
"How often does she hope for that phone call, with unconditional love on the other end? I don't know her story. But it doesn't feel like a huge leap to assume she's lost those who should love her the most and forever."
Dittman then urged such parents to empathise with what their children might be going through.
"Imagine that your child feels SO LOST FROM YOU that they sink into the arms of a complete stranger and sob endlessly just because that stranger is wearing a shirt offering hugs from a dad," he wrote.
"Think of the depths of their pain. Try to imagine how deep those cuts must be.
"Please don't be the parent of a child that has to shoulder that burden. I met WAY too many of them, of all ages, today."
He also said if anyone knew the strangers in the now-viral photos should tell them to get in touch if they need.
"Please let them know they can reach out any time they need a surrogate dad to talk to," he said.
"I'll be there."
The post soon went viral, garnering 366,000 likes, 263,000 shares and 38,000 comments - and counting.
"The thought of a parent turning their back on their child is completely heartbreaking to me," one person wrote.
Another commented: "Breaks my heart that there are somebody's children walking around feeling unloved and unwanted because of who they love. What a gorgeous thing to do even if only for a blip in time."
A third added: "Beautiful story. Love is everything."