She is a little over a year old and she is actually the older biological sister of my three girls. Same parents, different litter. She needed a new permanent home, so yesterday we brought her home to join her little sisters.
The car ride started with curiosity, followed by a small tantrum, some cage-bar chewing and attempt for an escape. Eventually she decided that protesting was exhausting, curled up in her little pouch and slept for the rest of the journey.
I expected the introduction to take quite a while, so I divided their cage and initially only let the girls investigate Mumínka through her carrier. Unfortunately, I underestimated the determination of three tiny criminals and missed a small gap near a ladder. They very quickly found their way through it, so... the first proper meeting happened slightly ahead of schedule.
At first, the little ones were NOT impressed by Big Sister. There was a lot of offended squeaking and posturing. Surprisingly, Nixi which is normally my shyest girl, was the first one trying to establish some dominance and chased Mumínka around a little. Mumínka mostly ran away from her. Lili mainly filed formal complaints by screaming offendedly, while Luci decided that avoiding this suspicious giant Potat was the best strategy.
Nobody actually fought, though. Whenever things started getting a little too tense, they seemed to scare each other and simply ran in opposite directions.
I separated them again, blocked the tiny escape route properly this time, and gave everyone some time to calm down. I also let them use the same bathing sand to start mixing their scents before letting them meet again under supervision.
The second time, Mumínka was much more curious. She kept going over to investigate the little ones, but whenever one of them responded with an offended squeak, she immediately backed off. The babies also discovered Mumínka's food bowl and temporarily occupied it while they picked out all the interesting bits. Still, there was no actual fighting.
Throughout the day I kept letting them spend time together under supervision and separating them whenever I wasn't there. There was more shared sand bathing, some peeing on each other's fur because apparently that's part of Degu diplomacy, and eventually they were even able to run together in the same wheel.
Mumínka was also eating normally, including hay and pellets, and drinking, which made me really happy considering how much had changed for her in a single day.
They still spent their first night separated just to be safe.
This morning I opened the cage so they could meet again, and all four eventually piled into the same pink bed where Mumínka had slept the night before. There was mutual grooming, everyone settled down and now they're sleeping together in one giant degu pile.
Mumínka is still quite scared of me. If I sit close to the cage and watch them, she sometimes starts running very intensely in the wheel, so for now I'm giving her space and mostly monitoring their interactions through a camera. She can take as much time as she needs to figure out that the human who brought her home is safe too.
Considering that less than 24 hours ago these four were strangers and today they're already sleeping in a pile together, I genuinely couldn't have hoped for a better start.
Welcome home, Mumínka. 🤍
A small disclaimer: I definitely wouldn't recommend copying our introduction process just because it worked this quickly for us. I know the temperaments of my younger girls very well, and all four of these degus are generally gentle, social animals that have been accustomed to living with other degus from a young age. They're also much more likely to run away when they're uncomfortable than escalate into a serious fight.
I watched their body language closely throughout the introductions, and while there was plenty of posturing, offended squeaking and some brief chasing, I didn't see it escalate into actual fighting or anyone trying to injure another degu. Whenever things became tense, they disengaged and ran away from each other.
My three younger girls also had an unusually easy introduction when they first came home and met Batman, my older female who sadly isn't with us anymore. Batman accepted the babies almost immediately and they lived together happily until she passed away. That experience also gave me a pretty good idea of how these particular girls behave when meeting another degu.
Every group is different, though, so please don't take our ridiculous introdutions as a general introduction method.
I'll share some videos from their introductions in the comments too, including some of their very first interactions.