As you'd expect, the Keeping Up With The Kardashians star was one of the first people to meet little Saint, the son of Kim Kardashian West and rapper husband Kanye.
Khloe, 31, chatted briefly about the new addition to the family while live streaming with fans on her official app overnight.
"My little nephew was born he is so cute and so perfect," said an over the moon Khloe. "I love him and mommy and daddy are doing fantastic."
Saint West was born via natural delivery at a hospital in Los Angeles on Saturday, 5 December. He weighed 8lbs 1oz.
The tot's unusual name is believed to have been chosen because his parents view him as a blessing considering Kim's difficult pregnancy. As well as having placenta accreta once again, she needed a procedure to turn Saint around from the breech position ahead of the birth.
Saint is the fifth baby born to the Kardashian sisters: Kim is also mum to daughter North, two, while Kourtney has sons Mason, five, and Reign, eleven months, and daughter Penelope, three.
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