Don't play chase him/he chases you games with him.... because it is tons of fun and he will really like it. BUT when he grows up, he will think everyone "just loves" him "chasing them". And when they run - which they will, by the way (regardless of all the advice to the contrary) he'll just chase them harder and run even faster. And then all the neighbors will be afraid of him... they will "make up stories" about him on Cub Scout outings while sitting around the fire and "everyone will know 'someone' who was actually caught and eaten by him".