He is starting to be a little wary of some things, but not many. We have these wooden planks over part of the sidewalks on our street – they're doing some extensive sewer and water work on our block – and he doesn't want to walk on them. He will stop when he hears weird noises, but doesn't run away. He's also starting to look less like a roly-poly baby and more lean and bulldogy. He's still adorable. About 4 months and 26 lb.