Donald Hugh (or Hughy) Grant was born in 1870 in the town of Negapatam (Nagapattinam). Unlike his father, he worked for the South Indian Railways as an engine driver (now known as loco-pilots) and later retired as a loco-foreman from Donakonda Junction in Bezwada (Vijayawada).

We gather that he worked in the Madras and Southern Maratha Railways which was then, a branch under the South Indian Railways. 

Farewell address given to Donald Hugh Grant at Donakonda. This was seemingly printed on a fabric of silk.

On 19th October 1891, Donald Hugh Grant tied the knot with Flora McKenzie at Trichinopoly (Trichy)

Their marriage certificate.

Farewell given to Donald Hugh Grant likely at the Donakonda Railway Institute (he is seated at center right, his wife is seated center left and the new foreman is seated in between).
Recent picture of the railway institute (Picture Courtesy: Google Images)

We understand that Donald Hugh Grant led a prosperous life travelling across South India (Vizag, Donakonda, Trichinopoly, Hubli ) in his official capacity before moving to Bangalore, after retirement.