It is based on James Herriot 's first two novels , If Only They Could Talk ( 1970 ) .
It Should n't Happen to a Vet ( 1972 ) , and was given the same title as the 1972 US compilation volume of these two novels .
It is based on James Herriot 's first two novels , If Only They Could Talk ( 1970 ) and It Should n't Happen to a Vet ( 1972 ) , and was given the same title as the 1972 US compilation volume of these two novels .