Cate Blanchett was mistaken for Kate Upton by her sons' school friends.

The 50-year-old actress has sons Dashiell John, 17, Roman Robert, 15, and Ignatius Martin, 11, and daughter Edith Vivian Patricia, four, with husband Andrew Upton, 53, and revealed that on her sons' first day at a new school, the other students heard her name was Cate Upton and got confused.

Speaking on 'The Late Show with Stephen Colbert', she explained: ''When they first started [at the school], because my husband's surname is Upton, and my first name is Cate, I was down as Kate Upton. And Kate Upton is a very attractive actress and swimsuit model

''Their friends at school said, 'Oh my god, is your mum Kate Upton?' And the boys innocently said, 'Yeah!' So 20 kids were waiting at the first day of school pick-up. I arrived, and you could feel the disgust and disappointment.

''I can disappear in my day job, but I can't be Kate Upton.''

Kate, 27, is an American actress and Sports Illustrated swimsuit model.

Meanwhile, Blanchett has previously called Edith ''an extraordinary blessing'' and said the little girl has changed their family for the better since they adopted her in 2015.

She said: ''She has been an extraordinary blessing for all of us. It's a huge part of what I am and what I want to do. I can't help it, it's part of my instinct.

''Edith woke up in the middle of the night and said: 'Will you pick me up from school tomorrow?' I'd sort of said to the babysitter, I really can't pick her up, because I didn't want to be late for [a magazine interview]. But I was really happy to be able to.

''Being able to do what you say you're going to do - there is nothing better. I love it when I wake up thinking that there's something on, and then I see that I've got the day wrong, and all of us can just stay in our pjs...''