Gen. Thomas and Frances Kellogg Thomas never did have children. Gen. Thomas' brothers and sisters were:
John William Thomas, who married, lived both in Southampton and Norfolk Counties, don't know if he had children.

Judith Elvira Thomas, never married
Benjamin Robert Thomas, married Virgina, had children, lived
in Vicksburg, Mississippi.

Annie Thomas, never married as far as I can tell.
Frances C. Thomas, never married.

General Thomas' parents were John Thomas and Elizabeth Rochelle.