So by this logic, if a man who spends his life lecturing on child safety and development turns out to be a serial pedophile, this is irrelevant and ad hominem?
Focusing on his pedophilia would be an ad hominem argument. Whether it is relevant depends on what we are talking about, I actually don't know why you brought relevance into this since it's fairly pointless to talk about relevance is some unspecified general way.

We should take his ideas of childhood at face value? Please.
An ad hominem argument rejects the ideas based on something other than the ideas themselves. Objecting to an ad hominem argument suggests that we should do the opposite of taking someone's ideas at face value.

She wrote at length about the evils of charity and public welfare. She posited that taking from the productive and giving it to worthless peopel such as widows and war veterans was parisitism and derisible. She preached selfishness as the ultimate good. So you don't see any connection, and cognitive dissonance between her accepting public welfare at the end of her life and her entire life's work? Really? Don't be coy.
It's all relevant to the ad hominem, yes. And the ad hominem is relevant to itself I suppose, like I said it's fairly pointless to talk about relevance is some sort of general unspecified way.

She preached that selfishness was the ultimate good. That is so incredibly open to criticism that I can't see why anyone would bother focusing on her. If she hadn't accepted social security, would that say something significant about whether selfishness was the ultimate good? I think it would be just as wrong.

More generally, it is very common that we know what is right, and say to other people what is right, and don't do it ourselves. This makes hypocrisy a fairly useless ad hominem to make. People preach morals that are right, and don't live up to them, that doesn't make them not right. And in this case she was preaching one that wasn't right, and didn't live up to it. That doesn't say anything about whether it was wrong or right.

Criticizing ideas directly is a lot more worthwhile.