If you want advice - well, you didn't say exactly what kind of help you envision.
Depending on how you feel about him, curious, or maybe wondering what it would be like to get to know him a little better at this late date, you could write him a letter that leaves the door open in a cautious way.
For instance, you could say that it's interesting news, but you were surprised to hear from him since he wasn't forthcoming when you needed help over the years. Then you could say, if you like, that you're not sure how you could be of help, but you were wondering what kind of salary he had in mind.
And then you wish him well with his plans. And send him a picture of your child.