Alexandar Grant

[AllanUK]

So Janet/Jessie Milne gave birth to James, Alexanders son

Yes, James was born illegitimate and as James declared on his marriage certificate, his father was reputed to be Alexander Grant. I doubt if you will ever find written documentation to prove this. Not the end of the world, just about every family historian has an ancestor where they can not prove 100% on something.

[AllanUK]

she went on to marry David Duff and then went back to Alexander Grant?

There isn't any evidence to prove that she had a further relationship with Alexander Grant.

[Neale1961]

she went on to marry David Duff and then went back to Alexander Grant?

After James was born she married David Duff.
She DID NOT go back to Alexander Grant who was married to someone else and had his own large family.

[Mackenzie777]

I have a marriage cert of Alexander Grant marrying Helen McWillie, father stated as William Grant reputed Elspet  Garden Deacesed?

I cannot find Alexanard marrying anyone

[Neale1961]

I have a marriage cert of Alexander Grant marrying Helen McWillie, father stated as William Grant reputed Elspet  Garden Deacesed?

I cannot find Alexanard marrying anyone

 Completely wrong Alexander Grant.

[Mackenzie777]

Thankyou for that, back to the drawing board for me.

[MonicaL]

Why are you back to the drawing board?

AllanUK and Neale1961 have provided you with good leads to follow up on 

Monica

[Mackenzie777]

I more than appreciate their help Monica, when I say  "back to the drawing board" it was tongue in cheek as I obviously had gone down the wrong road completely.

[MonicaL]

Good luck with it all 

Monica