Dutch uncle

To talk to any one like a Dutch uncle is to reprehend him, to use the patruæ verbera linguæ.

1837.  If you keep a cutting didoes, I must talk to you both like a Dutch uncle. Each of you must disperse; I can’t allow no insurrection about the premises.—J. C. Neal, ‘Charcoal Sketches,’ p. 201.

^*_*^* See Notes and Queries, 3 S. iii. 471; 6 S. ii. 473.