our boys seemed to get along from day one. Max the oldest still has accidents in the house and Milo has learned on his own to go to the door. in fact, we have a set of bells that hang on the door for them to ring and Milo the youngest learned right away how they work. Max just sits and looks at them
they are great companions for each other and I can't imagine one w/o the other. I would love to get a little girl next year but I am not sure how they will react. Max was five months old when his little brother came to live with us so they were pretty close in age....3 months apart. I don't know if bringing another one in will be too much to handle or not ??