We have never seen her angry but we have seen her thinking about everything.
Yes, the important thing is that she is told the truth. If she is told to full truth, there is much for
her to be sad about, but very little to be angry about. Or if she is angry, it should be towards the ones that infected her mother in the first place and then kidnapped her, murdered her beloved adoptive family, then tried to sacrifice her in an effort to kill her father and grandfather. They are the ones responsible, not her father or mother, who may have made a series of stupid mistakes, but in the name of love, not malice.