I did say earlier that I had found Rosalind's birth - I've been avoiding saying her name as against Rootschat policy as probably still living. details removed by Moderator Whilst you can see the birth entry to view birth certificate you would have to purchase it as a cost of £12.
So, at this point, I would say both the Neill children were indeed the children of Allan Neill - sometime between 1940 and 1942 he joined the army and possibly transferred to a camp in England. Whether Margaret moved too is speculation but she was certainly here when she had the 2nd child. We can only speculate on what happened next but she must have returned to Scotland at some point for the 2nd. child to end up there but I personally doubt Carl Olson was in the picture as early as 1942. For whatever reason she returned to England at some point where she was living as Margaret Olson (per electoral rolls) in 1946/1947 Wandsworth with Jean R.G. Milroy (a witness to her 1st wedding).
We simply can't know or second guess what the situation was - clearly her marriage to Allan Neill broke down but exactly when/why we don't know.
Annette