Uses the same quiet, judgement-free testing approach as WEEKDAYS and MONTHS: click a relative to see the term, click “Test me” to have it blanked out, and type it letter by letter (space reveals a letter if you're stuck). No marks for right answers, no scolding for wrong ones.
The real point of this one is the aunts and uncles. English, French, German and Spanish just say uncle/aunt regardless of anything else. Croatian splits uncles by which side of the family they're on (stric vs ujak) but not by age. Thai splits by two different things at once: whether the aunt or uncle is older or younger than your parent, and — only for the younger ones — which side of the family. Older aunts/uncles get the same word (lung/pâa) regardless of side; younger ones split into paternal (aa) and maternal (náa). Cousins, after all that, are just one word in every language here.