I'm very concerned about my budgies. I've had Baby for a little over half a year (he's much younger; his bars have only recently receded fully) and Shamrock about three months, and neither of them have ever been aggressive. Baby sometimes nibbles my fingers a little bit too hard when he's excited (I'll usually put him by one of his chew toys and he goes nuts on it), but that's about the extent. Baby follows Shamrock around all the time, but Shamrock's never seemed to mind. He'd sometimes snap at Baby whenever he was too fed up, but it was never really hostile. No angry noises or fights. But in the past two or three days, they've fought at least four or five times. I've been present for (probably) all of them, and I've been able to separate them quickly. As soon as they're separated, they go back to being joined at the hip as if the fighting never happened.
The first two times were likely Shamrock being annoyed by Baby's squishing up against him, but the past two times I've no clue. I was laying in my bed when I heard startled bird noises so I jumped up and separated them and everything was normal. The third and fourth seemed to be completely spontaneous. One got near the other and everything went berserk. The fifth time was probably the most understandable. I held out my arm and one came over. The other got excited and flew over a liiiitle bit too far to the left and landed on the other.
They still cuddle and preen each other as they usually do and eat together, but I'm worried that when spring break ends they're going to get into a fight and I won't be able to separate them. I've considered putting Baby in the smaller cage, but I'd rather not unless I absolutely had to. Any advice?