Not sure if I can help you but I have some information on Leckie's from Greenock. My great great grandmother was Mary Leckie from Greenock. She married James Doherty in Greenock 24 May 1850 and I have a copy of the Marriage Certificate. This was I understand Mary's second marriage but I have no details on her first.
Mary and James had three boys Francis (Frank), Peter and James. While I have no verification of this yet my mother has told me that she believes James (senior) left his wife and the three boys. Frank continued to be known as a Doherty or Docherty as it was changed to. However Peter and James both changed their names to their mothers maiden name i.e. Leckie. Peter had two boys Andrew Leckie and Peter Leckie.
I have no dates on them yet, but as Frank was born in 1850 and had his first child in 1868 a birth date of 1870 for what might be one of his nephews seems a possibility.
I have one futher piece of evidence Andrew Leckie. Frank's second child, James Doherty (he seems to have changed the name again) was married in 1902 in London and one of the Witness' shown on his marriage certificate is Andrew Leckie. I am making this assumption that this is his First Cousin but cannot be sure.
In any event the Docherty and Leckie's in my tree all come from Greenock and I have a number of certificates of birth, marriage and death. I visited the own last Summer to view some of the houses and address' I have.
While Leckie is a not uncommon name of course there may be a link of some kind. If you are interested in me sending my tree you can either email me or check my online version on www.ancestry.co.uk