a little bird told me

alternative a little birdie told me

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

   Let’s just say I know because a little bird told me.

   5 more examples

   […] I did lately heere, / How fleck and his make use their secret haunting, / By one byrd, that in myne eare was late chaunting.

   [1546, John Heywood, chapter V, in Julian Sharman, editor, The Proverbs of John Heywood. […], London: George Bell and Sons, […], published 1874, →OCLC, part II, page 121

   I vvil lay ods, that ere this yeere expire, / VVe beare our ciuil ſvvords and natiue fier, / As farre as France, I heard a bird ſo ſing,[…]

   [c. 1596–1599 (date written), William Shakespeare, The Second Part of Henrie the Fourth, […], quarto edition, London: […] V[alentine] S[immes] for Andrew Wise, and William Aspley, published 1600, →OCLC, [Act V, scene v], signature L, recto

   VVell, vvell; I had a little bird told me all this—

   1780, [Sophia] Lee, The Chapter of Accidents: A Comedy, […], London: […] T[homas] Cadell, […], →OCLC, Act III, scene [ii], page 45

   'Yes,' replies she, 'and what do you care about them?' / 'It's very much I care,' replied I, 'for a little bird has whispered a secret to me.'

   [1833, [Frederick Marryat], chapter I, in Peter Simple. […], volume III, London: Saunders and Otley, […], published 1834, →OCLC, page 6

   ‘Is Harry Fortescue in love with Florry Carlton?’ asked Lady Charity. ‘A little bird told me he was as good as engaged to her.’

   1872 July, [George Webbe Dasent], “Three to One: Or Some Passages out of the Life of Amicia Lady Sweetapple. Chapter XLVIII. Lady Sweetapple Sees Lady Charity, and Hears Something of Edith Price.”, in M[ary] E[lizabeth] Braddon, editor, Belgravia: A London Magazine, volume VIII (Second Series; volume XVIII overall), London: Robson and Sons, […], →OCLC, page 104

   Synonyms: rumour has it, word has it