More sneaky cognitive biases. Hindsight bias, Loss aversion and Recency bias. Parents in particular frustratingly seem to suffer from hindsight bias where everything becomes blindingly obvious as soon as a child has dropped the glass/fallen over/bumped into someone. Though careful is not so useful after the fact.
Photographs of John and Jackie Kennedy openly expressing their affection, which was a rare event. After the Cuban Missile Crisis and especially after the loss of their son Patrick, their relationship became stronger and Jack started to shed his aversion to public displays of affection. The last photo is heartbreaking, as it was taken only a couple hours before JFK was assassinated and is one of only a few taken of them holding hands.