Justin Timberlake’s mum has reportedly been nagging the star to have children ASAP with girlfriend Jessica Biel.

According to Fox News, Justin’s mum Lynn Harless has been telling friends she doesn’t want to be an “old grandmother” and since she had the singer at the age of 20, she thinks at 28 he’s more than overdue to become a dad.

A source revealed that Lynn was talking up procreation at a party recently: “She was telling people that now Justin’s so successful career-wise, he needs to start thinking about other things like getting married and having kids.

“She wants to run after her grandkids while she’s still got plenty of energy for them and thinks Justin will regret it if he leaves it too much longer.

“But Justin isn’t interested. He tells her to cut it out whenever she mentions the idea. He’s happy as he is.”

Justin has been dating actress Jessica for two and a half years but she recently told Allure magazine that she had “no idea” if she wants to get married and be a mum, adding that she still thinks she has “a lot to do, careerwise.”