Welcome to the group @dansybelle.
From when the mines started in the North east there has always been stories of families moving from the South to find work in the Northern mines but never heard any stories etc. of miners moving South to find work in mining as all the mines would have been in full production in 1944 when WWII ended.
The Durham Mining Musem site has a list of all the Durham & Northumberland collieries. This is a direct link to the alphabetical entries of mines in the area :- http://www.dmm.org.uk/colliery/index_a.htm
Under the Morpeth name there are only two entries :-
Morpeth Banks Colliery Pegswood, Morpeth
& Morpeth Moor Colliery
There were two collieries in Bedlington :-
Doctor Pit
& Bedlington/Sleekburn 'A' pit
and these two pits had links with other pits in the area eg. Cambois, Choppington, West Sleekburn, Barrington & Bomarsund, Stakeford.
For a family to move to the South withoput work or links to relatives would seem to be a very brave move.
I am not a member of a genealogy site but expect them to have access to to the latest census records ie. 1921 and birt h records that might help you identify area the family lived and occupation.