For someone who was known for courting publicity and revelling in the limelight for the early part of her career, Paris Hilton sure knows how to keep a secret.

The former socialite and heiress has surprised fans with an Instagram post that apparently announces the birth of her first child with husband Carter Reum.

The post features a baby's fist wrapped around Hilton's manicured thumb, with the caption "You are so loved already" and accompanied by a blue heart, leading many to assume that the baby is a boy.

The 42-year-old Hilton married businessman Reum in 2021, and the baby is believed to have been born via a surrogate.

Celeb friends including Chrissy Teigen, Kris Jenner, Lindsay Lohan and Demi Lovato congratulated the couple, while Kim Kardashian said "So happy for you guys!!! 🤍"

Hilton is set to publish her memoir, 'Paris', in March.