How many children did Mary and Percy Shelley have together?

Mary Shelley and Percy Shelley had four children together, but only one survived infancy.

* Clara Shelley (17 September 1817 – 24 September 1817)

* William Shelley (7 January 1819 – 7 June 1819)

* Percy Florence Shelley (30 November 1819 – 5 December 1889) - Only surviving child

* Clara Shelley (27 September 1821 – 27 September 1821)