how can the forum tell you why he barked. so he barked at the neighbors but he
didn't do anything. the bark could have been him saying hello or pet me or
him saying "listen, i learned to bark. listen to this". he found his voice.
he may bark at anything because he can. pay attention to his bark.
you'll figure out what his barks mean.
"Life Without A Dog Is A Life Unfulfilled"