Mandatory Credit: Photo by Trf Images/REX/Shutterstock (9473041g) Paris Hilton, Kathy Hilton, Nicky Hilton Paris Hilton and Nicky Hilton out and about, Los Angeles, USA - 21 Mar 2018 Paris Hilton and Nicky Hilton celebrate their mother, Kathy Hilton's birthday at The Palm Restaurant in Bevely Hills