Kristen Bell refuses to get ''stressed out about the holidays''.

The 'Frozen 2' star - who has daughters Lincoln, six, and Delta, four, with husband Dax Shepard - knows people want to have a ''perfect'' Christmas but she's taking a more spontaneous approach in order not to get overwhelmed by the details.

She explained: ''It's tempting to think that everything has to be perfect. But if we decide at 2pm on Christmas Eve to order takeout instead of cook, I will have a smile on my face.''

But there are some traditions the family will stick to, such as carefully opening presents and chatting about their gifts.

Kristen explained to Women's Day magazine: ''Dax introduced the idea of opening gifts on Christmas morning from youngest to oldest, which I really like.

''I'm able to talk my daughters through who gave them each gift. I try to reiterate that these presents don't just fall from the sky; they came from a thoughtful individual whom we need to thank.''

The 39-year-old star has spoken to Lincoln about the existence of Santa Claus, explaining the festive figure is part of ''an imaginary game we play because it's really, really fun.''

She said: ''I pictured her in a more adult situation where she had a sinking feeling in her gut and wanted to ask [a] question.

''Was I going to pat her on the head and go, 'Stop thinking about that, I already told you, it's fine, believe me,' or would I want to produce the kind of person who goes, 'I'm sorry, I really do need more information on this?'''

While Delta still believes in Santa, the 'Good Place' actress has promised to be upfront with her too when the time comes.

She said: ''When she says to me, 'Is this person a real human being?' I will have the same conversation with her as I did with Lincoln.''