Another tip for you which will require another letter:-
If John Hanlon is receiving a pension or contributing pension benefits, the National Search Unit at Human Resources Development Canada (HRDC) will attempt to locate him in their records. If their records indicate that the person is deceased, there may be a beneficiary listed. In either case, staff at HRDC will attempt to contact the individual or the beneficiary on your behalf.
Full Name ;
Date of Birth;
Last known address;
Relationship between you and the individual to be found; and
Reason for the search.
Please send your request, with your name, address and phone number to:
Human Resources Development Canada
National Search Unit
333 River Rd, 12th Floor, Tower "A"
Vanier, ON K1A 0L1