The Other One (2017)

After Colin Walcott drops dead at his birthday party, his wife Tess and daughter Cathy discover he had a long-term mistress Marilyn by whom he has daughter Cat. Furious, Tess throws out Colin's belongings while Cat is angry with boyfriend Marcus over a text he sent to another girl. When the two half-sisters meet, they argue over where to scatter their father's ashes which leads to police intervention; they also learn that he might have been having an affair with yet another woman.