This profile is protected so I cannot add parents. However his parents are documented in his wife's diary, available online here:
http://www.fadedpage.com/books/20120712/html.php#CHAPTER_I
General Simcoe was the only surviving son of Captain John Simcoe, R.N., of Cotterstock, who married Catherine Stamford on 8th August, 1747. The marriage took place in Bath Abbey.