Totally left field here...I notice you mention the address Caerbragdy.
In may interest you to know that in March 1931 my paternal grandfather (William John Corbett) murdered my pregnant grandmother (Ethel Louisa - nee Jones) at 48 Caer Bragdy Caerphilly/Glamorgan by cutting her throat with a razor. He was executed at Cardiff prison in August 1931.
All the best with finding your relatives
Angela