Recent­ly, there has been a spate of let­ters to Ann Lan­ders from moms con­cerned about sex­u­al­ly aggres­sive girls pur­su­ing their teenaged sons — lit­tle temptress­es hang­ing out on the front stoop, or call­ing in the mid­dle of the night, that sort of thing. Don’t these girls know, the moth­ers ask, that it’s a boy’s role to do the chasing?