'The ipm of Margaret Corbet, recorded 16 Henry VI (c1439) is indexed as follows:
Margareta, quae fuit uxor Roberti Corbet de Morton armiger' defunt'
and showed her as holding Shawebury, Salop.
From the indexed entry, we see that she is NOT called Margaret Corbet, only Margaret, formerly wife of Robert Corbet. Equally important, her husband had predeceased her.'