There was a Gabriel and Elizabeth Brown Galt family in Portsmouth prior to the Civil War. They had one son, Gabriel Alexander Dickie Galt, bc 1830 or 1834 and d 6/8/1908 in VA - a surgeon who served in the CSA. Gabriel Sr died about 1836. Elizabeth remarried at least by 1850 Census to an Edward Thurston Blumire.
Have more info on Galts of Williamsburg and Norfolk. Am looking for Gabriel A D Galt in 1900 to find a birth date.