Sons Dad

Why would you do that?

Because in your own words he was controlling and violent...

He also clearly isn't interested or wouldn't have disappeared in the first place

I wouldn't try. He's decided he doesn't want contact not you and you can't force a relationship to work.
My ds had not seen his father (who was physically, emotionally, financially abusive to me) since he was 18 months old his fathers choice. When ds was 14 he asked me if he could contact him - we did it together and they met twice his father was obviously not interested and no further contact has occurred it was upsetting to ds but at 14 was able to rationalise and discuss the situation at 5 your dc would probably struggle more with the repeat rejection as its difficult to articulate at 5.

Seriously op your dc - and indeed any dc - need 1 decent parent only to be a fully functioning adult - and your dc has you...
Why would you invite such a person into your lives?
My dd grew up with no df - she is amazing and successful and feels she most certainly did not miss out by not having a flakey shite df around..

Why would you want someone like that in your child’s life?

As someone who is currently in court trying to protect their son from a violent and controlling man, please count your blessings that he's not in your life. Do not invite this man back in to your child's life.

Honestly if I could have my controlling ex away from our sons I would he is toxic poisonous and a waste of oxygen

Don't invite it into your life

The damage that a controlling, violent and disinterested man could do to your son’s life is huge. And to yours. As it keeps coming up for you, I guess you feel that this man could add something to your son’s life, what do you think that is? Although I don’t think it could ever be worth the risk, personally.

I think better for the parent not to be around than to spend their childhood with unfulfilled promises and lack of interest. My ex was half hearted from the outset, had minimal contact with DD for the first six years (as in, a few hours in total). Hasn't seen her or made contact (she's nearly 23) except for once when she was 20 when he suggested meeting up - she said it would be like meeting a distant relative and similarly awkward, and didn't meet him (he lives overseas).

Hard to tell but she seems very balanced and philosophical about it, and has no desire to see him. We have always had a good relationship with his mother though.

Why would you put your son in contact with someone you know to be violent?

@UnknownEB he could contact you through the courts if he really wanted to.

I do actually get where you are coming from but don't do it. You don't need a violent man in your DC life.

Ime anyone can find anyone if they really try...