[TOMT][Movie][1980s] Possibly made-for-TV film about a white boy and a Black boy — organ transplant implied?

Hi everyone,
I’m trying to remember the title of a movie I saw as a child, most likely in the 1980s. It was definitely American, and it might have been a made-for-TV film. I remember it being set in the 1960s or 70s.

The story centers around two boys who are close friends — one white (grandson of a wealthy landowner) and one Black (the son of a worker, maybe a farmhand). The white boy had a serious medical condition — I think it was a heart issue, though I’m not completely sure. His grandfather didn’t oppose the friendship.

At some point, the Black boy mysteriously disappears. It’s strongly implied that he was used in some way for a medical treatment for the white boy — possibly an organ transplant. It wasn’t shown directly, but that’s what I remember feeling was suggested.

I’ve searched for this movie off and on for years with no luck. If this rings a bell for anyone, I’d be incredibly grateful for any help or guesses. Thanks in advance!