Simplify the following text for a Grade 7 native English-speaking person.
Original: He married Maria Antonia of Spain ( 1729 â `` 1785 ) , youngest daughter of Philip V of Spain and Elisabeth Farnese , on 31 May 1750 at Oulx and later had twelve children .
Simplified: He married Infanta Maria Antonietta of Spain ( 1729 â `` 1785 ) , youngest daughter of Philip V of Spain and Elisabeth Farnese . They were married on 31 May 1750 at Oulx and later had twelve children .