The 33-year-old reality TV star, who is ''honoured'' to grace the cover of the fashion bible's April issue, has revealed the couple's big moment was left somewhat sullied by their nine-month-old tot North West after she urinated on her rapper dad while taking a family picture for the magazine.
Discussing a close-up shot of the family lying on a couch, Kim told 'Late Night with Seth Meyers' last night (25.03.14): ''North peed on Kanye in that shot. He was trying to tell me. I had to get up and clean him off.''
Kim - who has longed to appear on the cover of Vogue for many years - also explained how she kept the photoshoot top secret from all of her friends and family, including her sisters Kourtney, 34, and Khloe, 29.
She said: ''They were a little suspicious. My mum [Kris Jenner] knew because we used part of her house, but I told them it was something for Kanye. I don't keep the best secrets.''
Kim appears in a gorgeous wedding gown on the cover, while Kanye, 36, is pictured lovingly caressing her from behind.
The reality star gushed over the history-making cover, adding: ''I knew it was happening, of course, but I didn't know it would be the cover. I'm just so honoured.
''Kanye's the first rapper, I'm the first reality star, [and] we're the first interracial couple [to land the cover].''
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