Ever since Kiwi (my green/yellow) started becoming mature (she's almost 2 years old now), I've noticed her chest tends to stick out quite a bit compared to Ben's. It seems a little weird to me. Is it abnormal? I thought budgies should be more streamlined. I'm attaching a photo. It seems to be slightly bigger than it used to lately, but not much. I could even be wrong about that.
Is she just fat? She eats, poops, flies and acts normally like she always has. Plenty of poop, trust me lol.
Sometimes it's even more pronounced depending on her posture and position, like so:
She's very active and not acting out of the ordinary.
EDIT: For comparison, here's a picture of her three months ago in May. It looks the same, so it's not like this is a new thing:
EDIT 2: Okay, so I went back even further to look. This one is from SIX months ago in February. It still sticks out, but less than it does now. Is this something I should be concerned about?