Justin Timberlake said he’s been “practicing” to have more children in the future, but wasn’t quite clear on whether he’s actually serious.

Meanwhile, the Can’t Stop the Feeling singer shares 18-month-old Silas Randall with wife Jessica Biel, and wishes for him to “stay that size.”

Speaking on the Trolls premiere in Los Angeles, he said: “Silas is a year and a half … want him to stay that size.”

When asked if he plans to grow his family, he shared: “I’m having a lot of fun practicing.”

And the 35-year-old star had previously confessed that fatherhood has “changed everything,” adding: “It changes everything. You literally wake up and look in the mirror and go, ‘I have no idea what I’m doing!’

It’s crazy. This new appreciation for both of them, her and him, it’s humiliating and it’s humbling at the same time … You watch her realise she has a gear she [thought she] didn’t have and then you go, ‘Woah, yeah.’ …

I would have never written a song like ‘Can’t Stop the Feeling!’ [if I wasn’t a father]. I don’t know that it was directly inspired to be something that my son could listen to of mine, because there’s a lot of music he can’t … at least not yet … [but he was an influence].”

Justin also feels more positive about life since the arrival of his son: “I’d be leaving out the whole truth if I didn’t say having him shaped what the song actually is. [Having a child] gives you a different insight.

It’s like ‘The Matrix,’ man. You open a door and there’s this whole other world on the other side of it. And you look back through the door at the other world and you’re like, ‘What was I doing there?'”