Lee Unkrich planned the emotional furnace scene in 'Toy Story 3' after imagining his family on a crashing plane.

The 50-year-old filmmaker helmed the third instalment of the hit Pixar franchise which nearly saw iconic characters including Woody, Buzz Lightyear, Ham, Rex, Slinky, Jessie and Mr and Mrs Potato Head nearly perish in a furnace.

But he admitted he had to imagine himself and his family dying and what he would do in his last moments but wasn't worried about it being too intense for children.

Speaking to The Daily Telegraph newspaper, Unkrich said: ''A lot of people asked me 'aren't you worried that this is too intense for children?'

''But I wanted it to ring emotionally true. I'd just want to hold my family close, and we'd face it together. Kids are more resilient than we give them credit for. When adults experience strong feelings, they naturally want to protect their kids from them, but experiencing good and bad things is part of growing up. And the safest place to experience the most troubling of all is movies.''

Now Unkrich has helmed the new Pixar movie 'Coco' alongside producer Darla K. Anderson, which follows the story of Miguel who finds himself in the colourful land of the dead and he unlocks the real story behind his family history.

Although the film - which is set in Mexico - deals with family loss, Unkrich revealed he received some backlash from parents who claimed the film wasn't in line with their ''own religious beliefs''.

He said: ''Some parents weren't completely on board with the idea of their kids seeing the film because they felt the ideas we were exploring were not in line with their own religious beliefs.

''If you take your kids to see 'Star Wars', it doesn't mean you're endorsing a belief in The Force.''