An Instagram account in Rocco Ritchie's name has branded Madonna a "bitch".
While 15-year-old Rocco - whose father is Guy Ritchie - deleted his account on the picture-sharing app earlier this year, a new account set up in his name describes him as a "Son of a bitch".
The account is set to private but features a close up of Rocco's face as its profile picture. It is not clear if the Instagram page has been set up by Rocco or not.
Madonna and Guy are currently locked in a bitter custody battle over Rocco, who left his mother's world tour last year to live in London with his father.
A source close to Madonna told the Mail on Sunday newspaper: "If this is his new account then clearly comments like this show he's in a delicate place and highlights the fact he needs to be in an equally supportive relationship with both parents.
"The fact it has been set up at all, even if it is just a prank by one of his friends, shows how public their feud has become. For Madonna, it is proof their relationship needs to get back on track as soon as possible."
Meanwhile, a High Court judge previously urged Madonna and Guy to come to an "amicable solution" as soon as possible to avoid any more of Rocco's "fast receding days" of childhood from being plagued by the custody disagreement.
Mr. Justice MacDonald said: "I renew, one final time, my plea for both parents to seek and to find an amicable resolution to the dispute between them.
"As I observed during the course of the hearing, summer does not last forever. The boy very quickly becomes the man. It would be a very great tragedy for Rocco if any more of the previous and fast receding days of his childhood were to be taken up by this dispute.
"Far better for each of his parents to spend that time enjoying, in turn, the company of the mature, articulate and reflective young man who is their son and who is a very great credit to them both."
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