Freeman's new novel is Tides.
At Lit Hub she tagged six "novels that explore the blurry psychic boundaries of sibling intimacy," including:
Daisy Johnson, SistersRead about another entry on the list.
This lyrical, gothic novel follows teenage sisters September and July as they take refuge, after an unnamed incident, in a dilapidated family house in the North York Moors. Their mother, a writer of children’s books, disappears for days at a time inside her room and the girls, only ten months apart (but merging their birthdays after September decrees it) seem to exist in a state of mind-body-meld that belies something far more disturbing than your average sibling bond. When September loses her virginity on the beach, for instance, July feels the pleasure and pain as viscerally as if it were her own. July, the younger sibling, is our narrator for the majority of the novel, and we slowly see, through her eyes, the way September, the eldest and more domineering of the two, begins to possess her, to ‘wear [her] like a coat.’ The house too, starts to ooze and engulf and terrify, until the final intoxicating reveal.
--Marshal Zeringue