So the whole family was in White Creek in 1850. That's good information. He would have been 27 in 1840 and should have had 2 or 3 kids by then. 1840 doesn't enumerate every one's name, right? But maybe he would show up? The problem is that w/o his wife's name we can't tell him from the other John McDonald. But the other one seemed to have stayed in Glastenbury all his life. I'm thinking out loud, sorry.