Mrs. Wentworth is Lexi's grandmother, who suffers from diabetes, and wants to see her granddaughter happy. Lexi cares for her grandmother, taking care to help her manage her diabetes. Mrs. Wentworth helps to rekindle the friendship between Lexi and Sienna, and gives to Lexi the old family diary of entries by past generations of sirens. This better helps Lexi to understand who she is.