Goody-goody gumdrops

The phrase "Goody-goody gumdrops", which I remember being used in the mid-1950s, was apparently (according to www.whirligig-tv.co.uk then go to 'Whirligig') the catchphrase of Humphrey Lestocq (of 'Mr Turnip' fame).

I recall both these characters and concur with this suggestion.

Goody-goody gumdrops goes back to at least 1887
in America, common in the 1930's. Also note a product called "Heisel's Goody Goody Chewing Gum"
from 1892. C.t. Heisel Chewing Gum Co, Cleveland

Have you details of the 1887 citation please? I can find 'goody, goody' and 'gum drops' from the 18th and 19th century respectively, but can't place 'goody, goody gumdrops' before the 20th.