Thank you all so much.
I have looked up West Kilpatrick and found it on a map and I will check the SP indexes for a birth of a William Bell. (though I suppose if he existed he could have been born in Ireland if Maggie was there for a while and was pregnant at the time of the census.
Thank you Kiltaglasson for the information on the births. With 3 Irish grandparents I am much more familiar with the irishgenealogy website and before that used geni.nidirect.gov.uk to purchase actual records. (I only use it now to search using mother's maiden name to get childrens names and dates then switch to the irishgenealogy site.)
How much does it cost to view a SP record? I think I will open an account to view some of the records you have all found for me.
I have a record for a Norman Bell aged 42, with wife Jean (aged 43) arriving from Sydney in Feb 1951. The address he was going to was 70 Barne St, Clydebank. So this seems a possibility now and his wife should? be listed on the death record.
In NZ the death records also listed children, though not names, just age and sex.
There was another Norman Bell, seaman arriving from New York in 1938 and he gave an address in Hartlepool. I did not find him in 1939.
I will look up Thomas Irwin Bell in Lancashire. (Thank you Rosie and Monica) I found a record for another Thomas Irwin Bell and wife Mary Louise Cook as parents of a Marcia Lynda Bell who married in Washington in 1951. I am pleased I can discount that one now.
And I can check again for Thomas Bell in 1911 using the Clydebank location. (Thank you Kay99) Perhaps the couple were separated so he listed himself as single. There are too many Thomas Bells to look for his birth in Ireland but now at least I can hope he stayed and died in Scotland.
My DNA match does not have a tree and has not replied to messages so though I think she belongs to this family, I could not be sure. And being female the surname Bell could be her married name. Though with possible marriages for 2 out of 3 of Maggie's sons, I think there is a good chance my match could be a 2nd or 3rd cousin as predicted by the amount of DNA we share.
Cheers.