1940s: IVORY BATH SOAP.
We move to a higher level of sophistication with this mass consumer campaign from Procter & Gamble. The setting is suburban middle-class -- mother stays at home all day doing "chores", with leisure enough to wallow in the bath all afternoon, and father wears a suit with a breast-pocket handkerchief.
She spanks her son when he comes home from school purely because she is stressed out through not using Ivory Bath Soap. The (surprisingly modern) implication is that one really ought not to spank one's son at all.
This is backed up by the headline, "I don't care WHAT the book says" -- probably a reference to Dr Spock's bestselling Baby and Child Care, which first appeared in 1946.