For me, the most important ones are my parents birthdays which are exactly 11 days apart (my dad's on the 10th and my mom's on the 21st) and also my grandparents wedding anniversary (on the 19th).
Another special occasion has been the wedding of one of my University friends, which I met 5 years ago, in a class and noticed her well put personality. She just speaks her mind if something or someone is just talking nonsenses and she, is THE BOSS. She is a very special person so she deserves all the happiness in the world by the side of her now-husband and their little princesses.