Maria Syphax was manumitted by Custis in 1826, along with her two children, and that year he granted her 17 acres of his Arlington plantation.

Although some of her land was initially confiscated with that of Arlington, her son William Syphax was able to use his connections and gain passage of a relief bill by Congress to return it to her.

There she met Charles Syphax, an enslaved man who oversaw Arlington House's dining room.

Carter and Syphax were married in the parlor of Arlington House in 1826, a privilege not allowed to other slaves Custis owned.

That same year Custis manumitted Maria Syphax and her two children and gave her 17 acres of the Arlington estate.