Why does Dee think Mama and Maggie don't understand their heritage?

because they don't change from it. In Dee's mind, Maggie and Mama lack the "Ethnic Pride

Explanation:

the chosen symbology is the 'sweet secret' which anna confesses on january 6th.

anne's thoughts on her mother are further indication of her growing maturity and of her feelings of isolation from her mother.

the homoeroticism of this passage led it to be excluded from early editions of the journal. this passage shows anne's simultaneous innocense about and fascination with sex. she's clearly aware and unafraid of being sexual, but at the same time is seemingly unaware that her homosexual feelings could be considered taboo back then.

hope this !