For me some are:
Eulalia (Westeria): Has the habit of testing her inventions and creations on herself, often getting herself hurt in the progress.
Charlia(Westeria): Has the habit of throwing herself into a blast to protect others.
Regan (1x1): Has the habit of ignoring her own health and body’s warnings.
Peckerhead plays with her straw when she’s upset.
Vic quotes facts and stats when they make introductions or don’t know what to say.
Ruthie has the habit of always apologising.
Let’s see… in my story, Ellie always rambles and goes off-topic. Her little brother, Karim, repeats words. Like: “The other day… the other day… the other day, I went swimming, and then, and then, and then…”