E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Wash your dirty linen at home (French). The French say the English do not follow the advice of washing their dirty linen en famillemeaning that they talk openly and freely of the faults committed by ministers, corporations, and individuals. All may see their dirty linen; and as for its washing, let it be but washed, and the English care not who has the doing of it. Horace (2 Ep., i. 220) says, Vineta egomet cædam mea (I do my own washing at home). Though the French assert that we disregard this advice, we have the familiar proverb, It is an ill bird that fouls its own nest.