Celebrity week in photos: Nicky Hilton introduces Lily Grace at a sip and see and more from the stars

December 23: Nicky Hilton introduced her and James Rothschild's daughter Lily Grace to their friends and family at a holiday "sip and see." Photo: Instagram/@nickyhilton/@parishilton

December 22: Elisa Johnson celebrated her birthday in NYC with her best friends. Magic Johnson's daughter dined at Vandal, and then continued her party at nightclubs Up&Down and 1 Oak. Photo: Scot Louie

December 22: Kristen Bell and her snow cutie Dax Shepard shared a kiss on the slopes in Mammoth, California. Photo: Instagram/@kristenbell

December 22: Family getaway! Kate Hudson, Oliver Hudson and their children packed it up and hit the slopes in Aspen for the Christmas holiday. The siblings were also joined by their parents Goldie Hawn and Kurt Russell. Photo: Instagram/@katehudson

December 22: 34 Forever! Shaquille O’Neal celebrated the retiring of his Miami Heat jersey at E11EVEN in Miami. Photo: Posh Panel

December 22: Broadway nights! Zac Efron took a trip to the theater to support his buddy Ben Platt during his Broadway show Dear Evan Hansen in NYC. Photo: Bruce Glikas/FilmMagic

December 21: Jane Fonda celebrated her 79th birthday with friends Lily Tomlin and Frances Fisher by returning to her activist roots and supporting the people of Standing Rock during the #BankExit Rally in L.A. Photo: Gabriel Olsen/Getty Images

December 21: Laurie Hernandez made her grand entrance during the Dancing with the Stars Live tour with partner Valentin Chmerkovskiy and Gleb Savchenko in Seattle. Photo: Mat Hayward/Getty Images

December 20: Ho, ho, ho! Katy Perry and Orlando Bloom offered some Christmas cheer to patients at the Children's Hospital of L.A. The couple dressed as Mr. and Mrs. Claus and passed out presents. Photo: Instagram/@katyperry

December 20: Working mama! Jessica Alba attended the opening of Laduree at The Grove in L.A. hosted by Rick Caruso in partnership with Baby2Baby. Photo: Donato Sardella/Getty Images for Caruso

December 20: Game time! Christie Brinkley and her son Jack cheered for the New York Knicks as they took on the Indiana Pacers at Madison Square Garden in NYC. Photo: James Devaney/GC Images

December 20: Special reunion unit! Law and Order SUV co-stars Christopher Meloni and Mariska Hargitay brought back Benson and Stabler for an epic holiday selfie. Photo: Instagram/@chris_meloni

December 19: karlie-kloss got virtual with her family during the 4D VR Sleigh Ride Experience at Samsung VR Presents: The Night Before in Herald Square in NYC. Photo: Llya S. Savenok/Getty Images for Samsung

December 19: New parents Kevin and Danielle Jonas helped fulfill holiday wishes for families impacted by medical events through the #AflacHolidayHelpers program in NYC. Photo: Diane Bondareff AP/Invision

December 16: Lily Donaldson added a little extra edge to her look at the LOVE Christmas Party hosted by Katie Grand and Poppy Delevingne in London with her blackout Timberland boots. Photo: Benett/Dave Benett/Getty Images for Birley / LOVE