Uninvited (2019)

She's here to shake things up. When three estranged sisters reunite at their stepmother Nancy's funeral, they are introduced to Ella Hughes and Danny D, a mysterious duo who claim to be Nancy's shunned biological children. While Nancy never mentioned any other family to the three siblings, they have no reason not to believe Ella and Danny. They may be a little sinister, at first anyway. Danny and Ella quickly work their way into the lives of the three sisters, using sex to turn them against one another in an attempt to get their hands on the family fortune.