In today’s edition of Keeping Up With the Kardashians, we’re amused to report that Kylie Jenner — reality-show star, occasional model, noted lip-kit proprietor — showed up at Christina Aguilera’s birthday soirée last night dressed as … a younger Christina Aguilera. No, not the bubble-gummy “Genie in a Bottleâ€Â Aguilera, but rather the “Dirrtyâ€-era Aguilera best known for powerfully crooning in boxing rings and fiercely gyrating in metal cages. While we’d usually be wary of revisiting Halloween costumes, this repeated getup came at the specific request of Aguilera, with Jenner captioning one of her Snapchats: “When XTINA wants u to dress as XTINA for her bday you do it!!!†Seems fair.