there are NO certs until 1877 - in the late 1840's the law re registration of marriages (as recorded in Parish regs) added the requirement to note father's names + occup - some parishes noted this a little earlier than others as some bought English registers which had required this since 1837.

Look at the family in 1851 and try to account for all parties in the household + their birth parishes etc - Esther even named her illeg child John David (john after the father, david I suggest after her father - david is uncommon for the Manx)