pid of grandchild or xterm -e foo process?

[RANDALL SCHRICKEL]

I think this is a single question, just phrased two different ways for the two
groups. How can a process find the pid of its grandchild (exec'd from an exec'd
child); OR how can a process that execs an xterm with the -e option find the 
pid of the process running in the xterm? I'm sure I could do it somehow with the
grandchild talking back to the original process, but then I'd have to change 
each of the (20 or so) possible grandchildren. I'm running the code on an HP 
9000 835S with HP-UX 7.0, X11R3, and Motif on an HDS X-Terminal. Thanx.