Kourtney Kardashian 'not OK' after son Reign has his long hair shaved off

Kourtney Kardashian's youngest son is sporting a new hairstyle and the reality TV star isn't impressed.

"I am not OK," the mother-of-three captioned the photo of Reign Disick.

In the Instagram pic, the five-year-old is seen rubbing his newly shaved head, where his tresses used to sit past his shoulders.

RELATED: Kourtney Kardashian holidays with North and Saint amid Kanye West's Twitter tirades

Kardashian, 41, has previously been trolled online for the length of her son's hair.

After sharing snaps from the family's Easter holidays users attacked the mum for not giving her son more of a trim.

"Bruh cut your son hair…smh," one user commented on the photos.

"Most gorgeous hair on Earth," Kardashian replied to the social media troll.

"Anyone who says otherwise ABCDEFG," she added, using the now famous Keeping Up With The Kardashians catch phrase.

Kardashian shares three children with ex-partner Scott Disick — their eldest son Mason is 10 years old and daughter Penelope is eight.

While Disick also features on the reality TV series, the eldest Kardashian sister recently quit the series, announcing time away from the cameras after a brawl with sister Kim.