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'”.

You’ll never need coffee more than the day after “Yes Day!”. #fiveyearsrunning #wesleptinatent #inthebackyard #coffeeismyyesday #yesday #nationalcoffeeday #imgettingthehangofhashtags (“Yes Day!”– a fantastic children’s book by @missamykr)

A post shared by Jennifer Garner (@jennifer.garner) on Sep 29, 2017 at 7:44am PDT

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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