Poseidon's children were Theseus, Triton, Orion, Otus, Polyphemus, and Ephialtes.
Poseidon had his first three children, his first lady named Χριστίνα or Chrustane, his second a man named Βικέντιος: Vincent, and his third they said was a younger boy named Perseus but turned out as a lady Parseus or Διατηρώγια which ment Cherishette:to love. She was named this from her step mother Aphrodite. Poseidon had many children after his first wife who's name is unknown but they knew she was a a fortune teller or seere of orahas. He has many others unknown. Although legend has it that they say his children are alive today.
Thesus,Triton,Polyphemus,and Ephialtes
the function of Poseidons temple was for Poseidons honor.
Rhea.
cronus
Neptune
Cronus and Rhea
Triton
Rhea.
a trident
Amphitrite - It's stated in the Wikipedia entry (see related link) scroll down to the section on 'Consorts and children'
He doesn't had friends
Give it back to Poseidon.