The marriage between Grout and Bennett was the daughter of Edward and Annie Isabella:
29 September 1917, Parish Church St Nicholas Guisborough
Annie Isabella Grout aged 21 years, spinster, resident 25 Auckland Street, Guisborough, daughter of Edward Grout, potato merchant.
Thomas Bennett aged 22 years, bachelor, a miner, resident 52 Walker Row, Middlesbrough, son of William Bennett, a miner.
Yes a birth certificate should solve the problem but not at our rate of exchange at the moment, we pay R18.33 for £1. R169.50 for a certficate from here.

Regards
Ceeoh