Do you live in the US? I have no idea what happened to John Irving or who he married. He does not show up any where but on the 1840 census in Dumfresshire Scotland. One reason being that he probably, according to local gossip, may not have been Robert Irving's son.Janet Carruthers may have been pregnant when she and Robert married. That of course is the local gossip and how to prove if it is right or wrong I don't know. There is a family stone in the Churchyard at Dalton but he is not on it.
There is a John, a grandson on it but he died at 9 years of age. So could not be the John I am looking for. I don't even know whose son he was.
I believe the families were not listed until after 1840 and if you go into Mormon site you will find this family but the dates are all wrong.