Jennifer Garner just put herself through parenting hell, all because of a children's book.

Jennifer Garner has posted a makeup-free selfie on Instagram to make a statement about parenting.

The photo was taken the day after Garner and her three kids – Violet, Seraphina and Samuel – had celebrated a ‘Yes Day’.

‘Yes Day’ was started by children’s author Amy Krouse Rosenthal, who wrote a book with the same name in 2009.

Basically, a ‘Yes Day’ is a unofficial holiday on which kids can request activities they can indulge in with their parents – and their parents have to yes, within reason of course.

Which sounds like a lot of fun for the kids but really exhausting for the parents.

In her post Garner wrote: “You’ll never need coffee more than the day after ‘Yes Day'”.

Garner and her family have been celebrating ‘Yes Day’ for five years now. One of the activities they did this year was sleep in a tent in the backyard.

So yeah, we can definitely understand her need for a strong coffee.

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