early bird

a little bird told me

I received the information from a source which I am not prepared to disclose.

be a hundred years too early

To be so immature and unprepared as to have no hope of achieving an accomplishment.

bird in the bosom

A secret pledge that one makes for another.

bird of ill omen

A person who brings bad news.

bird of one's own brain

One's own idea or conception.

bright and early

(Very) early in the morning.

call it an early night

To go to bed or cease one's activities earlier in the evening than usual.

Christmas come early

Something very delightful or fortunate that is happening or has happened, especially earlier than expected.