My older one was really really calm when I got him (I think its a her but I'm just gonna go with him😂) home and I was expecting something similar with the new bird. Turned out that the new bird is extremely playful and vocal she keeps making different sounds which my old cockatiel never made. She doesn't know how to step on a finger or hand yet but she's learning. She is more welcoming to toys than my older one but she doesn't really like my hand being around her and nibs it until I take it away. My older cockatiel was soooo easy to deal with I thought having a flock of 10-20 cockatiels wouldn't be a problem 😂😂😂
My 5 month old is a little nippy too. But, she doesn't bite . Just nibbles. She likes playing gotcha Beak. Older cockatiel sometimes loses interest. But every bird has their own unique personalities.