Good Riddles

Question: A wise man once called me "the moist star", and in an infinite sea, I can be seen afar. I create motions in which you may ride on for sport, and am also used as a scientist's port. What am I?

Question: Soft and cuddly, I'll pull on your heart.
But take my last name and I'll tear you apart.

What am I?

Question: If you have two twins, three triplets and four quadruplets; how many people do you have?

Question: I attach to your hip and I sing all day.
All I want to do is play.

Question: Two children are born in the same hospital, on the same year, on the same day, and have the same father and mother. But they are not twins.

How is this possible?