Hi.I don't think Thomas Gilbert was born in India, although I'm pretty sure his father was.Here is a birth record that matches :
England & Wales, FreeBMD Birth Index, 1837-1915 about Thomas Gilbert Alder Name: Thomas Gilbert Alder Year of Registration: 1849 Quarter of Registration: Jan-Feb-Mar District: Hertford County: Hertfordshire Volume: 6 Page: 594 (click to see others on page)
This looks like Thomas living with the Parke family in 1851:
1851 England Census about Thomas Alder Name: Thomas Alder Age: 2 Estimated birth year: abt 1849 Relation: Grandson Gender: M (Male) Where born: Bengeo, Hertfordshire, England
Civil Parish: Bengeo Ecclesiastical parish: Rochester Town: Bengeo County/Island: Hertfordshire Country: England Registration district: Hertford Sub-registration district: Watton ED, institution, or vessel: 4a Neighbors: View others on page Household schedule number: 203 Household Members: Name Age John Parke 63b. 1788 Walden, Essex - Wine merchant Harriett Parke 52 wifeb. 1799 Pattundplace, Middlesex Charlotte Parke 24 dau b. 1827 Shepherds Bush, Middlesex - Miliner Sydney Parke 21 son b. 1830 Broxbourne, Hertfordshire - Shipman Ann Parke 18 dau b. 1833 Ware, Hertfordshire Frances Alder 3 g-son b. 1848 Guilford, Surrey Thomas Alder 2 g-son b. 1849 Bengeo, Hertfordshire
All the children were listed as unmarried, so the parents of Frances & Thomas are not there.
Here he is in the 1861 Census:
1861 England Census about Thomas G Alder Name: Thomas G Alder Age: 12 Estimated birth year: abt 1849 Relation: Son Father's name: Gilbert D Alder Mother's name: Ellen F Alder Gender: Male Where born: Benger, Hertfordshire, England [Bengeo, Hertfordshire, England] Civil Parish: Bedford St Paul Ecclesiastical parish: Holy Trinity Town: Bedford County/Island: Bedfordshire Country: England Registration district: Bedford Sub-registration district: Bedford and Kempston ED, institution, or vessel: 8 Neighbors: View others on page Household schedule number: 98 Household Members: Name Age Gilbert D Alder 37 b. 1824 Calcutta British Subjects - Agent for Wine, Spirits & Tobacco Ellen F Alder 34 wife b. 1827 Broxbourne, Hertfordshire Thomas G Alder 12 son b. 1849 Benger, Hertfordshire Louisa E Alder 14 dau b. 1857 Chapmoreston, Hertfordshire Frances J Alder 13 dau (sic) b. 1848 Guilford, Surrey
In 1871 Thomas is no longer living at home:
1871 England Census about Gilbert Alder Name: Gilbert Alder Age: 47 Estimated birth year: abt 1824 Relation: Head Spouse's name: Ellen Alder Gender: Male Where born: Calcutta, India Civil Parish: Romford Ecclesiastical parish: St Andrew Town: Romford County/Island: Essex Country: England Registration district: Romford Sub-registration district: ROMFORD ED, institution, or vessel: 5 Household schedule number: 15 Household Members: Name Age Gilbert Alder 47 b. 1824 India, Calcutta (BS) - Mortgage money lender Ellen Alder 42 wife b. 1829 Broxbourne, Hertfordshire Frances Alder 20 dau b. 1851 Guildford, Surrey
Here is a passenger list record that could be him:
Canadian Passenger Lists, 1865-1935 about Thos Alder Name: Thos Alder Gender: Male Age: 23 Estimated birth year: abt 1850 Date of Arrival: 8 Jun 1873 Vessel: Nyanza Search Ship Database: View the 'Nyanza' in the 'Passenger Ships and Images' database Port of Arrival: Quebec and Montreal, Quebec Port of Departure: London, England; Plymouth, England Roll: C-4528 He was traveling alone, listed as a "clerk".