Susannah's birthdate: 11th May 1837
These look like the family, all in Halberton:
Samuel baptised 17 Jan 1836 to William & Mary
William buried 18 Jan 1836 age 39
Samuel buried 20th Mar 1836 age 6 months
It seems strange, but I suppose there's no reason why she couldn't have baptised her son the day before his father was buried

He presumably died at least a few days before the burial.
Mike.
PS: No mention on Samuel's baptism that his father had died.