It is a custody battle that has grown so bitter even a judge has begged Madonna and Guy Ritchie to make peace.
For four months, the former A-list power couple have fought over the future of their son Rocco, who is refusing to return to New York to be with his mother.
And now the singer has reportedly been left devastated after a social media account apparently set up by the 15-year-old has - very publicly - branded her a bitch.
The Instagram account in the name of "Rocco Ritchie", describes Rocco as a "son of a bitch" in a biographical description written just below a close-up picture of him.
Madonna, 57 - who will fly to Britain on Tuesday to see her son for the first time since before Christmas - is understood to be "deeply concerned" for Rocco and keen to get their relationship back on track.
Although the account's name, image and biography are public, all the pictures shared are private, prompting speculation that it does belong to Rocco. The picture on the page changed three times last week, and all appeared to be selfie-style close-ups of the teen's face.
Rocco has been absent from social media since January when he deleted his public Instagram account, which had 140,000 followers, reportedly after his mother shared a picture of him wearing his long hair in bunches.
However, friends say he has since set up another private account and that he has made Madonna one of the few close friends and family allowed to view the pictures he shares.
It will not be lost on Madonna that the Rocco Instagram account echoes an incident last month when the star allegedly called Ritchie a "son of a bitch" during an onstage "meltdown" in Australia.
Last night a source close to the singer said: "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."
If successful, Madonna's trip will be the first time she has seen Rocco since he failed to return to New York after visiting his father for Christmas.
She and Ritchie have been locked in a bitter custody battle ever since, with Rocco determined to relocate to Ashcombe House, the Wiltshire estate his film director father bought with Madonna in 2001.
The source continued: "Madonna will do anything to see her son again. She has realised that, as he won't come to New York, she will have to come to the UK to see him, which is why she is flying over on Tuesday."
Madonna was due to see Rocco as soon as her tour ended on March 20, but he surprised her by flying to the Maldives to spend Easter with his father. The singer is preparing to open up her rarely visited London residence, although she is yet to receive confirmation that Rocco will meet her.
The source added: 'Madonna is having her house opened up and she will sit in it until he comes to visit. She is determined and focused. She's very concerned for his wellbeing. She has been exercising every day to make sure she is in perfect health for when they meet.' Spokesmen for Madonna, Ritchie and Rocco refused to comment last night.