The 31-year-old model Instagrammed a pic of her surprise for Legend on Sunday, which involved her getting totally naked and meeting him in Boston, where he's set to play a show at the Blue Hills Bank Pavilion on Monday as part of his Darkness and Light tour.
... And there was cake, too.
"Successfully surprised John with a secret trip to see him in Boston :) gift level 10/10," Teigen wrote alongside a photo of her in the buff and holding a delicious-looking cake reading "Happy Father's Day."
"In all our time together (11ish years!!?!?) I cannot believe how much he has grown as a man and a husband," Teigen wrote. "To see him go from big goals to big ideas to big wins and the love of so many makes me so so happy. 10 years ago, I didn't think he could get better, then I got to see him as a father. I don't know how or why Luna, my family and I got so lucky in this life but I will stop questioning and just be grateful. I love you so much, John. Happy Father's Day."
Of course, Teigen also gave a sweet shout-out to her own father, sharing a picture of him walking her down the aisle on her wedding day in September 2013.
"Can't forget the first important father in my life," she wrote. "The man who never stopped working to make sure we had the best life possible. I was so proud to hold your arm on this day and so proud to call you my dad every day. Love, your boogernose goober."
"We don't mind showing off our bodies -- we just feel like there's no problem being natural and nude when you're with the right photographer and it's done the right way," he said.