I am certain of these two generations who earned a living as "tailors"...

Thomas Joseph Sharp (born 1843 Ramsey - died 1926 Braddan) m. 1864 to "Martha" Taggart

their son...

Robert Sharp (born 1869 Waterloo, Ormskirk, Lancashire, England - died 1938 in Norfolk, Virginia, USA) m. 1888 St. David's Church, Liverpool, England to Mary Pinder Brooksby

I am guessing the "postman" Robert Sharp might be related as the father to Thomas Joseph Sharp:
being...Robert Sharp (1800 Malew - d. 1884 Douglas) m. 1822 Malew to Elizabeth Lewin (Born 1800).

So, am I correct in assuming this would theorectically link this Robert as the son of John Sharp & Ann Corkill born in 1779.

Are there any records that show the names of the parents? Any proof to link the generations for certain?

Again, thank you so very much for all the help. I do so appreciate it.