Now, even though I wrote a book on former child stars, I don't pretend to know the whole story. I don't know what happened to Coleman's millions. I don't know why a joint autobiography written with his parents discussed the night his mother gave birth to him, even though she evidently didn't—he was adopted.

But I know this: Coleman, who died today at age 42, couldn't lose it all if he never had it all.

When he was just 22 months old, it was learned a knotted-up ureter tube had blocked off, and essentially killed his kidneys. Until the age of 4, he relieved himself through two holes that doctors cut into his stomach. For a time, he was equipped with a pouch that the preschool-aged Coleman could manipulate to make it look as though he was peeing just like all the other boys. When he was 5, he underwent kidney-transplant surgery.

So, no, Coleman never had it all.

Even when you thought he had it all—when he was the biggest child-star of the late 1970s-early 1980s, when he was the kid who saved the then-struggling NBC, when he was earning as much as $3 million a year from Diff'rent Strokes and his far-flung enterprises—he didn't.

In fact, he only appeared to have it all precisely because he never had it all.

Following the kidney transplant, Coleman was put on a steroid regimen to guard against organ rejection. The treatment had two side effects: One, it stunted his growth; two, it made him the Hollywood ideal—the performer who can play younger, much younger. That Coleman could sell a punchline made him a talent. The fact that, as a 10-year-old, he could sell a punchline looking like a cherubic 8-year-old made him a phenomenon.

Hollywood has probably never taken more advantage of a disadvantage.

Diff'rent Strokes curse? Child-star curse? Coleman wasn't one for self-pity or excuses, and he didn't do curses. "I just happen to be one who has survived, who has survived being chewed upon," he once told me.

Coleman's determination was double-edged: Because he perservered, he spent more years as a former child star—as the ultimate former child star—than he did as a child star. He spent more years living down Arnold Jackson than he spent living it up as him.

One thing Coleman never seemed to spend time on, however, was trying to get back what he once had. Sure, he'd appear on your TV show or do your movie if the money was there, but he never seemed desperate, as former child stars can be, for a return to the spotlight. For a return to the good old days.

Maybe he knew he they were never that good to begin with.

(Originally published May 28, 2010, at 6:02 p.m. PT)