Tonight with your 5 to 8 year old
The prompt
“If there's one snack left and two people want it, what's the fairest way to split it?”
What to listen for
If they suggest splitting evenly or taking turns who gets the whole thing next time, that's solid, growing fairness thinking. If their fair solution somehow ends with them getting more, that's typical for this age, gently ask "would that still feel fair to your sister/brother?" without shaming it.
Listen for whether they mention who's hungrier or who had a rough day as a factor in fairness, that shows they're starting to weigh feelings alongside strict equality, which is a more advanced form of fairness.
If they say "I don't know," offer the classic "one person cuts, the other picks first" trick and watch their face light up.
What this tells you
Their idea of a fair split shows whether fairness currently means "equal for everyone" or "equal including me getting enough."