Pregnant Khloé Kardashian Calls Tristan Thompson 'Daddy' as They Wear 'Game of Thrones' Costumes

Pregnant Khloé Kardashian channeled the mother of dragons for Halloween — and Tristan Thompson also coordinated with a Game of Thrones costume of his own.

On Monday, ahead of the spooky holiday, the parents-to-be dressed up as Daenerys Targaryen and Khal Drogo, respectively, for a Halloween party with his Cleveland Cavaliers teammates, including Kevin Love and Dwayne Wade and his actress wife Gabrielle Union.

“That’s daddy,” Kardashian, 33, captioned a shirtless photo of her NBA boyfriend, 26, of over a year.

The mother-to-be’s costume featured a long platinum blonde wig with braids, fur coat and metallic silver bodice. Meanwhile, Thompson transformed into the leader of the Dothrak by wearing a long black warrior wig and beard, black eyeshadow and drew on some of Drogo’s infamous body ink with paint.

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GoT fans will remember in season 1 that Daenerys and Drogo married when her brother, King Viserys III Targaryen, sold her to her future husband in exchange for an army.

They fell in love and Daenerys became pregnant with Drogo’s baby, but the child was stillborn and deformed.

Last month, multiple sources confirmed to PEOPLE that Kardashian is expecting her first child, a baby boy, with Thompson.

“Yes, Khloé and Tristan are expecting and they are absolutely thrilled,” one source told PEOPLE of the couple.

“This is something Khloé has wanted for years and years and yet it’s more than that: She didn’t want it unless she was in the right relationship for it,” the source added. “This is such a wonderful moment for her: not only is she going to be a mother, she is going to be raising a child with a man she truly loves. Everyone is over the moon for them both.”

The baby news broke just four days after PEOPLE confirmed that Kardashian’s 20-year-old sister Kylie Jenner is also expecting her first child with her rapper boyfriend Travis Scott, 25. In addition, PEOPLE previously confirmed that sister Kardashian West, 37, will welcome her third child with husband Kanye West, 40, this winter via surrogate.