I got 2 more chow chows, my favorite dog breed. They had no particular jealousy problems between themselves because they were full sisters, littermates and I took them at 5 weeks. They just naturally found their own balance and didn't seem to mind sharing me. But even if they liked another person too, that person would never be allowed to stand between them and me. Nobody could. I kept them well controlled at all times, but I always felt very safe even when traveling 'alone', because they could turn on their wild dog act quickly enough. But they ate together, curled up to sleep together, and some people who saw them from a distance thought I had them chained together because they were seldom more than a foot or so away from each other.
I guess they could've been provoked to mutual jealousy, but I never believed in doing that. They were my family, to the point that when the vet finally came to the house to bury them for me, I turned away crying out that I wished he could throw me in there with them. You wouldn't want to know me for weeks after that, and I still cry when I look at their grave. They were placed as close together in death as they were in life.