Some people have had trouble with rambunctious kittens annoying mature cats; it's probably a good idea to make sure that there is somewhere (up high, maybe?) that the adult go to escape from the kitten.
It sounds like they are getting along well, though; I wish you that they will soon be very happy and very comfortable with each other.
It sounds like they are getting along well, though; I wish you that they will soon be very happy and very comfortable with each other.