DD is 4.5. This week has been my birthday, her best friend's birthday, DS's birthday and DSD's birthday. I appreciate that it must be quite difficult watching your mum and both siblings get lots of presents, cards, attention etc. and I have tried to not make DD feel too left out - she's had a small present to open on each of the birthdays and she gets a turn at blowing out birthday candles. Both her brother and sister have allowed her to "help" open their presents and cards. I have also been reminding her that in just over a week's time, she'll be getting more presents than she can shake a stick at 
Despite all of this, she has behaved really badly all week. We went out for a meal and she was so badly behaved, DH had to take her off half way through. She's been cheeky, playing up at bedtime, crying and having tantrums over nothing and deliberately winding up her siblings. She is no angel normally but on the whole, it has been out of character.
So, is this perfectly normal behaviour or am I raising a spoilt brat ?! Is it a phase (I seem to remember 4 being a particularly jealous and self obsessed phase with dsd) ? How can we handle it better ?