Who was the youngest son of Johann Sebastian Bach and the last of 4 to reach adulthood?
Johann Christian Bach (1735-1782) was the last of 18 sons overall (maybe 14 died before reaching 10 years old) of Johann Sebastian Bach (1685-1750) and the 4th to reach adulthood and carve out his own composing career, part of a massive and far reaching family of composers active in the 17th and 18th centuries.
JC was called the 'London Bach' because he spent the last 20 years of his rather short life in London, where he met and taught the younger Wolfgang Amadeus Mozart, who was on his musical wunderkind sojourn that also included Germany, France, the Netherlands and Italy and unfortunately like JC Bach (who died a few months after turning 46 on New Year's Day 1782) would also die young in his 30s.
JC was the only member of the Bach family to visit Italy and write operas.
The accompanying uploaded image of JC Bach is a portrait by one of the greatest English painters of the 18th century, Thomas Gainsborough.