Do you know where he served (sounds like you have his military records)? A list of children? Did he marry in India? My daughter has a few British India records available to her, and she'd be glad to help you look. This is what she found in a quick glance. I know that it's ten years off your death year, but she thought that it might be worth considering.
As I'm typing, she's taking a quick glance through the records. Doesn't appear that this particular John & Ann Northcott were having babies out there at this time. He must not have served very long out there, or the wife died and he just didn't remarry right away.
Anyway, if you're interested, just let us know what YOU already know, and she might be able to help.
British India Office Records, Deaths & Burials
Name: Marian Northcott
DOD: 19 May 1867
Burial: 19 May 1867 at Cawnpore, Bengal, India
Age: 2 years
Cause of Death: Scrofulous Enlargement of the Glands of the Belly
Occupation: Daughter of John & Ann Northcott, Drum Major, HM 101st
Name: Ann Northcott
DOD: 09 Jun 1867
Burial: 10 Jun 1867 at Cawnpore, Bengal, India
Age: 23-1/2 years
Cause of Death: Cholera
Occupation: Wife of John Northcott, Drum Major, HM 101st