Sounds like they're just settling in.
We have 6 girl piggies, and while they all happily spend the day in the run, there are 3 seperate sleeping places.
GP 1&2 (oldest girls at 2.6 - and mine mine mine - I got them for Mother's Day!) sleep in a traditional hutch in the garden, moved into the garage when it's too cold.
GP 3&4 (belonging to dd1 and ds, age about 7-8 months I think) sleep in a big indoor hutch by the patio door.
GP 5&6 (belong to dd2, though she generously "shares" them with dh so he doesn't feel left out!) are currently sleeping in a smaller indoor hutch on the landing, they're 11 weeks.
In dry weather they have a ginormous run in the garden with 3 seperate piggy boxes, but it's quite common to find all 6 in one box together (with their bums hanging out! In damper weather I set up a run in the kitchen
so I can play with them. Sometimes their outdoor run is on the patio with an edge over the grass if its a nice day but the grass is wet.
GP1 tends to be a bit bossy and occasionally chases another one - including her sister. GP2 spends a lot of time sitting on top of the piggy box, keeping an eye on things. The rest do lots of chasing around as well as eating, but it's always happy wheeking. Never had a fight or an injury.
The entire shebang is overseen by the House-Rabbit, Speedy MacReadie (he was a rescue and came to us with that name). That's really the reason for the runs - to keep him away from them. He's so much bigger and clearly you can't keep them together. Our garden is completely secure so he can't escape, and he spends a lot of his time "on guard" beside the run. He's been known to see off pigeons and magpies quite forcefully!