United Kingdom, April 4 -- Britney Spears' son has changed his last name.

Sean Preston, 20 - who Britney shares with her former husband Kevin Federline - previously used his father's last name but he recently updated his Instagram handle to Sean P Spears, dropping Federline.

There is no suggestion he has legally changed his name.

Sean Preston and his younger brother Jayden James, 19, had previously been estranged from their mother and lived with their father Kevin.

She has said that her marriage to Sam Asghari "felt like a fake distraction" to enable her to cope with being "cut off" from her sons.

In an Instagram post last August, Britney wrote: "We're just people so fragile and human the hardest years of my life were two sons gone f...