Louis Tomlinson has reportedly been banned from picking up his son from his house.
The One Direction hunk's relationship with former lover Briana Jungwirth - the mother of four-month-old Freddie - is said to have reached "rock bottom", with the final straw for the 23-year-old stylist being when the Steal My Girl hitmaker arrived at her house with his current girlfriend Danielle Campbell in tow.
A source told The Sun on Sunday newspaper: "Their relationship has hit rock bottom.
"He is not welcome at Briana or her family's homes anymore.
"Things are strained. Now he's picking up his son in a car park."
The 24-year-old singer - who began dating actress Danielle, 21, just weeks before Briana gave birth - previously had another dispute with her ex-lover over custody of Freddie but managed to settle the row hours before they were due to go to court so he could "formally establish paternity and give him access to Freddie".
It had been alleged that Briana has "gotten greedy" and has been demanding more money, preventing Louis from visiting Freddie and using the tot to land a better deal.
However, the pair came to an agreement which will allow Louis to see Freddie for several hours at a time but with no overnight visits yet.
Before relations turned sour, the History singer had already given Briana a three-bedroom home in Calabasas, California, and is renting his own lavish abode nearby in order to be close to his son.
He hasn't had a DNA test to prove paternity, but insists there is no doubt he is Freddie's father and he and Briana were dating exclusively when she got pregnant.
Briana's cousin, Ashley Jessica, recently admitted Louis and Danielle's relationship had "hurt" their family.
She said: "Yes, it did hurt us. But life is life.
"I mean feelings are feelings and you can't help that.
"You love who you love - it's just bad timing."