All I found on FMP is this, which confirms marriage.
Mary
Last name Grayson
Year 1819
Event date 23 Feb 1819
Place Fauquier, Virginia
Place as transcribed Fauquier, Virginia
Town -
County Fauquier
State Virginia
Country United States
Spouse's first name(s) Samuel
Spouse's last name Porter
Residence as transcribed Fauquier, Virginia, United States
Groom's father's first name(s) -
Groom's father's last name -
Groom's mother's first name(s) -
Groom's mother's last name -
Bride's father's first name(s) -
Bride's father's last name -
Bride's mother's first name(s) -
Bride's mother's last name -
Record set United States Marriages
Category Life Events (BDMs)
Subcategory Civil Marriage & Divorce
Collections from Americas, United States