I cannot get to the local records office, so could someone, if you are going there and have the time, look for the marriage of Margaret.
Maiden name unknown.
She marries a man called Vaughan, possibly a Thomas.
Margaret was born about 1796.
She has four children, they were born in Presteigne.
Last known address was, 47 Green End.
There is no husband showing in 1841 and by 1851 she is shown as a widow and a pauper.
Her children were
Alexander b about 1826
William b about 1826
Mary. b about 1833
Charlotte, b about 1834
ps Does no 47 Green End still stand?
I googled it and Green End, Presteigne still exists.