What would a royal birthday be without a new set of portraits? As is customary for the little ones' birthdays, Kensington Palace has released four new photographs of Prince Williamand Duchess of Cambridge Kate Middleton's only daughter, Princess Charlotte, in honor of her 5th birthday on Saturday. In the pictures, snapped by none other than her famous mom, the pint-sized royal wears a houndstooth dress by Zara.