I think I may have to agree with Norm on this one - that is a first.
As I understand, the MO provided no definite cause of death and there were no forensics linking the mother with crime. Under Scots law, w/o independent corroborating evidence I doubt the case would even made it to court.
In Scots law, we may have returned ' not proven' - we think you did it but we can't prove it.
I don't think she is off Scot-free ; imagine living with the fact that you did not report the child as missing for 1 month. I would imagine her life will be hell wherever she tries to settle - I think she may have to move abroad.
Odd family; odd case - but I think the right verdict.
Tragedy is no justice for the child.