So my girlfriend and I are planning on moving in together within the month. She would be moving in to my house where I have a 2 year old and a 1 year old (cats not children). My girlfriend has a 4 year old, a 3 year old, and a 3 month puppy. My cats have been to my girlfriend's house but have never interacted with the dogs face to face (they've seen them and smelled them). The puppy has been coming over just cause she cannot be left alone and is currently in the process of being "whipped" by the 2 year old cat. The 4 year old use to live with a cat but not like a free roaming one (was a roommate's cat that stayed in the roommate's room most of the time) and wanted to play with him but also understood what a hiss meant. The 3 year old literally doesn't care about anything but food and scratches. I am planning on doing the introduction method where you do it through a door, then a baby gate, then supervised, then free roaming but does anyone have any advice as to how to make the introduction easier?