On Thursday, the 54-year-old actor celebrated the London launch of his Casamigos Tequila with fellow co-founders Rande Gerber and Mike Meldman, as well as the release of Cindy Crawford's memoir, Becoming, at the Beaumont Hotel. (Rande is Cindy's husband.)
As for George's wife, Amal, she, unfortunately, had a work conflict and could not attend, so the Tomorrowland star graciously brought his mother-in-law, Baria, to the party instead.
A source close to the family tells ET that George and Baria get along really well and he was spotted giving her a sweet kiss on the cheek during the event. "They seem to have a great relationship and she looks like she was having a great time with the whole crew," the source adds.
At one point in the evening, George actually played bartender and made drinks for A-list guests including photographer Mario Testino, Jeremy Piven and Downton Abbey actor Allen Leech.