Hello and Welcome to our little 'help-line'.
I am going to answer part of your query here but have sent a note to our Administrator to set up a specific Forum for Morvah in the Parishes section.
You have come to the right place with your query regarding the Harry family of Morvah - but I can already see some things that need to be 'sorted out'.
My main connection with this family goes back to the 1734 Marriage of Hannibal Harry to Alice Trewheela at Madron.
Alice Trewheela was a sister to my direct ancestor Martin Trewhella who married Catherine Baragwanath at Towednack in 1724.
I have a cousin (now 74) in Cornwall who is a direct descendant of this family and, along with Carlene Harry, has done a lot of work on their history.
There are obviously things that I not yet confirmed and may be classified as 'work in progress' but I believe we have a lot of things fairly well sorted.
Now to your query - which is where I can see an anomaly already and I will try to make that my first priority which means I will have to start with your third item and then work back.
William Harry (1764) - from what we have been able to discover he was baptised at Morvah June 3rd, 1764 as son of EDMUND Harry and Elizabeth (nee TREMBATH).
William is, apparently, the William Harry buried at Morvah in 1826.
He married (1) Grace GILES at Sancreed November 8th, 1788 and had, by her, four children - Walter (1789-1864), WILLIAM (1791-1818), Edward (1793-
?) and Henry (1795-1872)
Grace was buried at Morvah February 14th 1796 as 'wife of William Harry from Sancreed).
In 1799 William then married Jane ROWE by whom he had another seven children of whom none was named William.
The key point here is that WILLIAM (1791) whom you refer to in your note appears not to have married.
So I will now give you a little detail about your Alice Harry and her family - as I know it.
Alice HARRY bp. Morvah 17th April 1814 d/o William HARRY and Mary (nee BONE).
She married Thomas Bottrell CURNOW at Morvah 8th August 1835 and apparently died sometime after 1895.
Thomas and Alice had eleven children but I have not, as yet, traced them beyond basic information received from Nancy Tonkin, Carlen Harry and Bill Curnow.
William HARRY and Mary BONE were married at Madron in 1813 and had 8 children of whom Alice was the eldest.
Mary was baptised at Morvah 3rd June 1792 as daughter of Benjamin BONE and Mary (nee GILES).
William HARRY was baptised at Morvah 2nd May 1779 as son of John and Alice HARRY.
John HARRY was apparently born at Madron in 1740 s/o John HARRY and Jane (nee THOMAS)
Alice HARRY was, according to Nancy Tonkin, born in 1738 and was daughter of Hannibal HARRY and Alice (nee TREWHEELA).
Would appreciate a little more information on your link back to William and Mary (Bone) Harry so that I may help you further.
There are still some things I need to find on these families but, to the best of my knowledge, what I have shown here is correct.
Keep a look out for this to be continued in a new section and I will do my best for you.