LifeLink of Georgia, an organ donation organization, sent the letter March 3 to offer condolences and share information about the lives the man's mother saved by donating her organs. The user posted it March 5, and it already has more than 360,000 views and 700 comments.
"My mother, is living through them," the user wrote on the post. "Its [sic] so wild to think they have a part of her, and has saved their lives."
The letter says the organs donated by this user's mother saved a 51-year-old mother of two who works as a cook, a 64-year-old retired father of three who enjoys the outdoors and a 51-year-old father of two.
Other organs will be used for medical research, the letter says.
Kaysha Cranon, a LifeLink spokeswoman, said her organization has been sending such letters to donor families for some time.
"It's a way for the family to know that their loved one has impacted other lives," she said.