Angela
Tried to find marriages for the McMurchie girls and had a little success but more a process of elimination - not one marrying a Moore.
Mary born 1860 married Alexander ECCLES December 1882 qtr 8b 794 West Derby (Liverpool). In 1891 they were living at Faulkner Square, Mount Pleasant district, Liverpool. Alexander was a Policeman. She died 1896 aged 36.
Jane Marchie married Salford March Qtr 1876 8d 169 to an Alexander Muldoon.
An Agnes McMurchie married December Qtr 1892 Bolton 8c 644 but cant find who she married, possibly a George Jackson. On 1891 Census there is an Agnes Murchie, servant, born 1834 in Bolton, born Braddan but age a little out?
Elener McMurchie still in Onchan, servant, 1881 census.
Cant find what happened to Janette mentioned in 1851 Census aged 6.
What were the names of William and Margarets daughters? Did they name one after his Mother maybe?
Next process is to maybe see who (apart from Jane as she married before William was born) isnt on say 1881 Census and if she is missing and as William is missing off this census as well then thats another angle to look at maybe.
Frustrating I know.... but hope this helps
Sandra