Validity: The premises faithfully reflect the passage's reasoning: the intentionality requirement (premise 1) combined with the fact that harms to the family are side-effects rather than purposely inflicted (premise 2) logically entails the conclusion that such harms do not constitute punishment.
Confidence: The argument is clearly laid out: the definition of punishment requires intentional infliction, and family harms are side-effects, so they don't count as punishment.