I have found a Charles Seaver (son of Eilinor and Nicholas Seaver) who married a Mary Powell. They had one son and five daughters. To confuse the issue, Mary (above) was the daughter from the marriage of Mary Seaver (sister of Charles above) and Jonathon Powell.
I feel that i must be getting close to making the connection with the Foxall family here, as our "signature" family christian name is in fact Powell. I am trying to trace the marriages and subsequent children of the Seaver and Powell families in the hope of tying up the connection.