The man who dresses the red carpet stars for Valentino, Carlos Souza, was himself feted at the Upper East Side home of Inga and Keith Rubenstein on Friday night. Guests who gathered at the Rubensteins’ elegant art-filled mansion to toast the birthday of the fashion dynamo — dubbed Valentino’s Brazilian Lion — included Valentino and Giancarlo Giametti, Ann Dexter-Jones, Carlos Mota, artist Anh Duong, Olivia Palermo, fashion editor Carine Roitfeld, Tamara Beckwith and David and Julia Koch. Souza, the worldwide brand ambassador for Valentino and CEO and creative director of Most Wanted Design, is next heading to China to carry on celebrating with his twin sons, Anthony and Sean.