Am researching the Harts of Philadelphia. Need information on a John Hart born in PA July 1819 in the Kensington section. His wife was Martha X. He died between 1870-1880. In the 1850 census, he had a Mary Hart, born in NJ, living with him, age 68 years. It's possible that this is his mother. There was also a William Hart, age 50, born in NJ, living with John and his wife in 1850. Any help in finding the parentage of John Hart would be gratefully received.