Has anyone seen my child?

By that I mean not physically seen my child but...I'll try and illustrate via a story of a lovely lady I used to work with.  The lady in question was, as I said, lovely.  She had been a teaching assistant at the school I was working at for a few months but on the day in question she had turned up late into the staff room and was looking really flustered.  Poor woman proceeded to burst into tears and when I asked her what was wrong she told me that she couldn't understand what had happened to her normally polite, kind and considerate son.  She went on to explain that he had turned into a horrible, rude and not very nice person.  At the time I was far away from being a parent so my reassurance that I was sure it was just a phase and that he'd grow out of it must have sounded ridiculous coming from me.  I now find myself going through the same thing with Toddler.  She used to be a really laid back person.  She really didn't care if another child wanted a toy that she wanted-She'd just go and find something else. Ditto with her own toys at home.  If I asked her to do something she'd do it-no problems with nappy changing, getting changed into clothes etc.  Now it seems everything is a battle.  If I say left, she says right and everything is peppered with whinging and/or crying. Of course I've heard people speaking many a time about 'The Terrible Twos' and it sure seems like they're upon us.  I've thought about that lovely lady a lot recently and hope her teenage son and she came out the other side fairly unscathed.