Lovato checks out footwear while shopping in West Hollywood. Plus: Reese & Jim, Matthew & Camila, Lady Gaga and more

POWER COUPLES

Double-date night? Matthew McConaughey and Camila Alves join Reese Witherspoon and Jim Toth as both couples leave their kids at home Thursday for the Art Mere/Art Pere for Livestrong cancer benefit, presented by Corzo Tequila, in L.A.