What are similarities and differences between hypnos and morpheus?

Hypnos is the father of Morpheus.

Hypnos was the god of sleep itself, most likely he put the gods and mortals alike to sleep. He is usually potrayed modernly as a sleeping god.

Morpheus is a god of dreams, he manifested himself in the dreams of kings and rulers in the likeness of men as a messenger of the gods. He is leader of the tribe of dream gods, his brothers and possibly uncles.