Suggestions to deal with a Father's Day fiasco...?

Since this happened to a friend of yours, I wouldn't think that you would personally do anything about it. If he is upset about this, maybe he could do something that I do with mine. They can be forgetful sometimes , so I know what this is like. On the appropriate day, I ring my kids instead of sitting around waiting for them to remember me. We have a nice chat, and that is that. I don't keep score of "who sends me a gift or a card ". I just call them and smile, have a little talk and then I go on my way. Your friend should try that approach - whether they were going to remember him or forget him, it doesn't matter when you make the call yourself.

I would have to know more about his circumstances.

He had 5 children from a previous marriage. Did that marriage end in divorce? Were the children resentful and blamed him for the break-up?

How old are his children now? Are they so busy celebrating Father's Day with their own families? Sad, but true, some children once they leave home, have a tendency to forget about their parents and don't realize we think about them and worry and care about them just as much as we did when they were small.

I'm glad at least one child remembered him on this special day. If the others felt they were too busy, how much effort does it take to mail a card or pick up a phone and call? They probably don't realize how much this would be appreciated.

I don't know how you found out about this. If he told you, obviously he was hurt by this, but it is not up to you to chastise the children, and no use for him to do it either. Unfortunately, when the parents die, the children who neglected them cry the loudest at the funeral. They moan, "Oh, if I had only........" The ones who showed their love while the parents were alive, can rest assured they did all they could. No guilt.

There is nothing you can or need to say - - nothing can change it - if they called only because you prompted it would that have been better? I would not want a call that did not emanate from the heart of the sender themselves -

It is definitely sad, likely unfair - as life can often be.

Don't dwell on it - let it pass as quickly as possible and never mention it again as the memory will be painful and unpleasant.