Judd Apatow has said working with Lena Dunham on Girls helped him collaborate with Pete Davidson on a new film about his issues following the loss of his father.

Judd Apatow: Working with Lena Dunham on Girls informed film with Pete Davidson

Judd Apatow: Working with Lena Dunham on Girls informed film with Pete Davidson

The Knocked Up film-maker, who wrote The King Of Staten Island with Davidson and also served as director, said he felt protective of the 26-year-old comedian as they wrote the screenplay that echoed his own experiences with grief and mental health.

The film tells the story of an aspiring tattoo artist who is struggling to move on with his life after the death when he was a child of his firefighter father.

Davidson was just seven when his own firefighter father died in the September 11 terrorist attacks.

Apatow told the PA news agency: "I have worked with other people who are willing to make themselves vulnerable and be very truthful, I've made movies with my kids where they were little and I wanted them to come across well on screen, and I would be terrified the entire shoot and the edit … what if I make my kids look terrible in this movie, what if they are humiliated worldwide because I did a bad job?

"And working with Lena Dunham helped a lot – she was always finding a way to be brave and vulnerable about all of the things that she felt and was going through, so I feel I've had a lot of years where people have been willing to do this and I was aware of what you need to do so that person feels like we all care and have his back."

Apatow said he was particularly proud of the way the film addresses issues of mental illness.

"I think it's always important to be honest about these things," he said.

"I was talking to some friends the other day and I grew up in the early '80s and no-one ever said they were depressed, no-one ever said they had anxiety, and I think we were all depressed and we all had anxiety and we didn't even have those words.

"We didn't know anyone would care about our feelings, it just wasn't how we communicated with each other, and I think about how many kids must have really been suffering because no-one's parents were sending them to a therapist, we were all just sucking it up.

"So I think it's great when Pete talks about these issues, I know it's very meaningful to people.

"I produced a stand-up special with a comedian named Gary Gulman called The Great Depresh, which was on HBO, about his struggles, and he got tens of thousands of messages from people who just said 'Thank god you are talking about it, it makes me feel so much better, knowing that you climbed out of it and that you're feeling better', so that is one of the things we are more proud of."

– The King of Staten Island is available to rent at home from June 12, from Sky Store, Amazon Prime Video, Apple TV & iTunes, Google Play and other digital retailers.