"I love you, you are the best cousin in the world."
Let's break it down:
* Te amo: This is the most common way to say "I love you" in Spanish.
* Eres: This means "you are" in Spanish.
* El mejor primo: This means "the best cousin".
* En el mundo: This means "in the world".
So, the entire phrase expresses a strong and affectionate feeling towards a cousin.