There are 7 Francis Kellys born in Dundee between 1875 and 1883, and without Birth Certs, he could be any one of them. The only tree on Ancestry is for a man born March 1880 who was kia in France in WW1
1882 Mar 4. Born Forfarshire
1898 Nov 11 Enlisted with Gordon Highlanders. No proof that it is our man
1921 May 18. RIC no 81071 & ADRIC no 1058 . ex-Soldier & Labourer
Posted to 4 Gds