There is significant truth behind the statement "everyone is fighting a battle you know nothing about". A conversation with my stepsister reveals how toxic parenting, favoritism, manipulation and emotional immaturity can fracture family ties - usually beyond repair. My stepsister was the scapegoat and I bounced back and forth from golden to lost child. All the assigned roles have their poisonous ripple effects.
It may help to first check out the episode titled "1 single revelation every BIG STEP she takes".