More on Keep One's Own Counsel from Infoplease:

• Keep One's Own Counsel - Keep One's Own Counsel (To). To be reticent of one's own affairs or plans. Source: ...
• counsel: meaning and definitions - counsel: Definition and Pronunciation
• Dictionary of Phrase and Fable: K - Definitions, origins, and illustrative excerpts for words, phases, and literary allusions starting with "K"