[4][5] Borthwick's younger brother Watty also became a footballer and his son Bill worked as a trainer for Everton.
[6][7] Borthwick served as a private in the Football Battalion of the Middlesex Regiment during the First World War and suffered a gunshot wound to the head at Delville Wood in 1916.
[8][3] He described his injuries in a letter to Bert Lipsham: "my head has been trepanned, as the skull was knocked in.
[3] After his retirement from football, he ran the Winslow Hotel, opposite Goodison Park.
This biographical article related to association football in Scotland, about a defender born in the 1880s, is a stub.