This. My kids are now the third generation enjoying the same Lego bricks. The oldest were bought by my great grandparents for my father, so these toys already

This. My kids are now the third generation enjoying the same Lego bricks. The oldest were bought by my great grandparents for my father, so these toys already involve five generations and probably will still be used for at least another couple of generations. As far as sustainability goes, Legos are incredible.