Not sure if there’s much I can add to this topic, and I don’t consider myself to be a particularly keen judge of character anyway, but after considering numerous details of Cera’s behavior in the first movie, I have come to two conclusions. Firstly, I think that Cera mainly acts rude and arrogant to protect her pride as a threehorn. (We all know how important
that is to her.) Furthermore, maybe I’m just interpreting the movie and Cera’s actions differently from other people (or perhaps I’m just outrageously oblivious), but outside of insulting Littlefoot and his mother and being seemingly apathetic towards Ducky, Spike, and Petrie when she leads them into the Burning Mountains, I really don’t see her as having been all that bad. :blink: (Stubborn, proud, boastful, and rash she may be, but certainly not deserving of a label like “b****.”)
When Littlefoot first meets Cera, she appears to have no qualms about playing with him. (Granted, we will never know exactly how the pair would have interacted had Cera’s father not prevented it; for all we know, he may have inadvertently saved Littlefoot from one nasty head-on collision.

) Even after taunting Littlefoot by repeating her father’s statement, “threehorns never play with longnecks” (my opinion is that she was just being impressionable), she hardly objects to playing with them in the hoppers’ pond. It is only after Cera is separated from her family that she refuses to associate with Littlefoot, and even that doesn’t last long.
I have always been disappointed that we never really got to see Cera’s (or Spike’s, or even Petrie’s, for that matter) “initiation” into the gang (if you get what I’m saying). But although she appears to largely keep her distance from the others for much of the journey, it’s obvious that she would rather travel with them than adhere to traditional threehorn doctrine and go it alone. (At the very least, she is accepting that it is safer to stay in a group, even if the other members of that group lack horns.

)
More significantly, when Cera is woken by Sharptooth’s roar the morning after sleeping in the footprint with the rest of the gang, the first thing she does is attempt to wake Littlefoot. If she had been solely interested in self-preservation, one would have expected her to immediately and silently race off, leaving the others to sate Sharptooth’s appetite. The fact that she bothered to raise an alarm says to me that she cared enough to not want such a fate to befall them.
It could also be argued that her apparent apathy for Petrie, Ducky and Spike while traveling through the Burning Mountains is attributable to her being angry after her squabble with Littlefoot (who appeared equally unconcerned for the others’ safety when they left to follow Cera); so much so that she didn’t notice that Petrie had fallen off her or that Spike and Ducky had been left behind. (I’m not entirely sure if this interpretation makes sense, but I thought I’d share it just the same.)
While my early memories of watching the original
The Land Before Time are dim, I don’t remember ever disliking Cera (though her father genuinely scared me). Somehow, even compared to the sequels, her behavior in the original movie never struck me as being all that horrible.