Help: Middle aged son lost his job, how much should I help?

[Etiene]

Our son (in his 40’s, married with school age children) has lost his well-paid job. He’s has taken it very badly and it will take some time to get a new job at his level, but they have a huge mortgage, etc. We’re retired and are happy to offer some help, but it could never be enough to cover his mortgage, etc. How far should we go in helping him and his family, at what point should we stop? If you were in his position how much help would you expect from your parents?

If the grandchildren are school age, both son and Dil should look at getting temporary jobs ( perhaps seasonal jobs). It is always going to be dangerous if just one person in a relationship works. Eggs in one basket and all that.
I understand your desire to help. That is a good thing to do, but both of them should show willing to work and help themselves as well.