In Charles Keller, an appreciation in a 2007 issue of People's World, there is frequent (and true) reference to Charles' life of ease thanks to his father's wealth. Charles never denied it, nor does the article claim that he did.
What it omits is how little it meant to him. He had no interest in banking, investments, capitalism. He couldn't be bothered to open the envelopes containing his bank and broker statements. I, his son, did that, and to a small degree managed what needed managing but riches and disasters came and went.
Ignored, some of his stocks climbed to great heights; others crashed. The ol' man was oblivious. I was horrified but ultimately not very helpful, alas. In the last decades of his life, Charles' assets dwindled nearly to zero. He lived on remarkably small sums, mostly pittances from Social Security. He was fine with it, no less happy than at other times in his life, and never concerned.
He just didn't think about it. His socialism was sincere.
-- Dan Keller, 2007