Hello "имя"!Happy birthday to you!
It's important day today! I wish you a lot of friends,happiness, love, luck, health,fun, good marks and great future."name",you are really good person.You so kind and clever.I happy to be friends with you. I really like to spend time with you."name", you are my best friend.
Wishing you a wonderful year!
Your friend,"name"
По-моему тут 50 слов или больше.