Howdy, evening...
I have a trio.
My history is, 3 sisters, one died, replacedwithafriend without bonding, luckily they got on fine. It's at that point they came to me. I now have buttercup, 5 years, Violet, 4 years and I have just bonded Millie, who isn't a year old.
The sisters were close, but the dynamics changed with a death, hence Millie. They have changed again and are still settling, but the oldest is head piggie, followed by violet then newbie Millie. Violet grooms buttercup, but can always be found to be with Millie.
They are fine, depends what type of day it is depends on whose with who but since Millie is still skittish it's no problem.
I have a ferplast 140 with a custom made half second level with no probs of fighting or disagreements. Buttercup is a teddy, violet a satin and Millie a coronet cross something.