We have a multi-dog home and there are pros and cons.
Two of our babies were puppies from different litters when we got them. There were a few months that separated them. They are very close. Our next dog was brought into the home a couple of years after these too and while he gets along with them, he is a loner when the three of them are together. Our last dog was brought into the home about a year after him, and they are closer together, and they do play with each other, however the two of them are independant and would rather have mom and dads attention instead of each others.
As a multi-group, if one is getting special out of the kennel attention for some reason, the other three create such a barking frenzy it is insane. Work as we have on quelling the barking it doesn't happen.
so we have the barking frenzy and they feed off of each other until the one who is out of the kennel goes back in to his kennel.
Plus they are all males - that should give you another clue - it can get a bit crazy here !