Hi anerob
I looks a distinct possibility that Ada's mother was Robina LAING by birth and was never married to any James LAING - though it is possible she married a cousin or a man who just happened to have the same surname? Just as possible she made him up, though perhaps a grain of truth in that his name was James! (If you have a marriage of Robina & James however, I do apologise!
for casting aspersions!)
1901: St Andrew, Dundee, AngusRef: Parish 282/4 , ED 20, pg 36
Address: 3 Crescent Street
Head: Robina LAING 40. Flax Spinner, b Strathkiness Fife
Dau: Ada LAING 16, Linen Weaver, b Dundee
1891: St Andrew, Dundee, AngusRef: Parish 282/4, ED 19, pg 31
Address: 16 Crescent Lane
Head: Harriet T LAING 18, Jute Winder, b Dundee
Sister: Robina LAING 30, Tow Spinner, b Strathkiness ---?
Sister: Ada LAING 6, Scholar, b Dundee
These are froma source which does not show the marital status. So a look at those original Census images to see what Robina says about that would be interesting.
Looking on IGI:
Harriet Thompson LAING was born 20 Jun 1872, Dundee
Parents were: William LAING and Robina DIAMOND
All children to these parents, William and Robina, on IGI are:
Robina LAING b 8 Oct 1860 St Andrews & Leonards Fife (Strathkiness comes in here)
Jane LAING 6 Jun 1863 Dairsie Fife
William LAING 14 Feb 1865 Cupar Fife
Hugh LAING b 8 Jun 1866 Cupar Fife
David Christie LAING b 17 Feb 1868, Cameron Fife
James Mitchell LAING b 8 APr 1870 Dundee
Harriet Thompson LAING b 20 Jun 1872 Dundee
Maggie Ann LAING b 4 Nov 1874 Dundee
I can't find a marriage of William LAING & Robina DIAMOND.
But it looks promising, that Aunt Meg was Robina's sister Maggie.
In order to see if James also had a sister named Margaret/Maggie/Meg - perhaps the birth cert of Ada to see if he was named on it? On whatever documentaion you have, what does it say is James' occupation, if any?
Cheers
AMBLY