Snuggle

Snuggle: verb

/ˈsnʌg.l ̩/ v [I usually + adverb or preposition]
to move yourself into a warm and comfortable position, especially one in which your body is against another person or covered by something

EX: The children snuggled up to their mother to get warm.
EX: I was just snuggling down into my warm duvet when the telephone rang.

Spanish: Acurrucarse

To snuggle up to sb, arrimarse a alguien
To snuggle down o up (in bed), acurrucarse (en la cama)