If you are a mistreated step-daughter, you can expect (a) your stepmother to try to kill you via her huntsman and, failing that, a suspiciously bright red apple and (b) your fairy godmother to turn up and make it possible for you to go to the ball after all. The important thing is you must be humble, kind to others and willing to be subservient for a bit before coming into your true inheritance. Any sign of arrogance on your part will immediately disqualify you for the "major rewards and happy ever after" prize that is so often on offer in the fairy tale world.
Do not be surprised by these and do listen to what they have to say. They are usually on the side of the good guys and can be very useful to have on aboard (Puss in Boots is a good example). But there are exceptions to every rule and if you come across something that looks grey and hairy and wears a dress your granny would wear, run away. Fast. It'll take the Big Bad Wolf a while to shake off that dress to pursue you so you should build up a good head start.