Like a real fight or just yelling at each other ? I notice while Kamila was away for her vacation Kristy was spending more time with Kayley, and when Kamila is there she is the one always with Kayley.
If they vanish it's because they are going out shopping or enjoying the city, or to the beach I think. In the house they only vanish when they are on the toilet or in the little wardrobe room..
That poor cat walking around keeps begging but not getting anything, I dont think the cats they have around outside is getting much food. I only saw Candy throwing some food to them one day at the terrace.