In 1814 Sir John's aunt, Harriet Simeon, sister of his father Sir Richard, married Sir Frederick-Francis Baker, who died in 1830 following an accidental blow from the sails of a windmill. It was their only daughter, Jane Maria, John Simeon's cousin, who became his wife in 1840, the same year that he graduated M.A., having been educated at Christchurch, Oxford. It was her brother who put up some of the money when Richard Godin Simeon was raising the first of his mortgages.