I've heard about this unique cultural aspect of the Manchus' child-rearing practices. Is this rooted in fact? Was this practice widespread? Or was this a slanderous myth?
As far as I'm aware, this was mentioned in "Growing Up: A Cross-Cultural Encyclopedia" by Gwen J. Broude, on page 303.
Quote from the book:
In China, Manchu mothers tickle the genitals of their little daughters and such the penis of a small son.
While I can't speak for the truth of this, I'd like to point out that this is not necessarily "slanderous". You are viewing this practice through your own cultural lens. And, if Ms. Broude is to be believed, sexual behavior involving children that would be weird to us is more common than we think.