In the 1930s families tended to be on the large side. The 2 child norm was not yet in vogue due to family planning advocates being treated like criminals and general public ignorance when it came to matters of procreation.
Often as not, several kids would transgress family rules and regulations and were spanked one after the other.
Punishments were seldom excessive and kids accepted their spankings on the whole, using this form of correction when they had their own families... Why..? because they knew from personal experience that it kept them obedient and well behaved rather than disobedient and downright rude.