I didn't prepare really.... We have only had our new baby for 1 week. I made sure I greeted Maggie ( our older baby) before letting her see her new sister. We than let them meet outside and slowly moved inside all the while talking sweetly to Maggie. There wasn't a problem at all until the 3rd day when Maggie realized Tilly was here to stay. The toys are our greatest problem, when I see one that is causing them to feel upset, I just put it on the counter for a few days before I give it back to them. Don't know if it will help but over all they really like each other. They sleep together since the 2nd night and love to play. It's soooooo cute,
I wouldn't go back to just one dog again.