I suggest you have a look at freereg, which lists the marriage of this couple (James HUSH and Mary PERRY) at Midsomer Norton in 1839.
Their first son was Thomas Benjamin Perry HUISH, almost certainly named after his maternal grandfather Benjamin PERRY.
You will also find baptisms for both Mary and James on freereg, both in 1817; one in Ashwick and the other in Midsomer Norton. Look for James under the variant spelling of HEWISH: his father was also a blacksmith.
I think you'll find that Mary's parents were Benjamin PERRY and Martha MARCHANT, married at Chilcompton in 1806. Mary had two brothers - George and John.
I hope this helps with your research.
Kind regards
Philip Candy
Toowoomba, Australia