Sandra,
Apologises I miss-read your first post, the Family 6 tree you mentioned, I have seen before but I'm afraid that the tree-owner is incorrect in regards to Richard Mortimer. That might sound pompous of me but they've confused a Richard Mortimer from Bradford with my distance relative who was born in Bristol and lived in Keynsham, the finer details don't match up. I've traced the Bristol/Somerset/Wiltshire Mortimers to about 1715.
Besides that thanks very much for your post.