Reese Witherspoon says her daughter's college applications felt like "an arrow to the heart"

She told Emmy magazine: "My daughter was applying for college back then, so it hit me like an arrow in the heart.

"It's so difficult to articulate what motherhood means, and there are so many passages in the novel that did."

Reese - who has Ava with ex-husband Ryan Phillippe and also has kids Deacon, 16, and Tennessee, seven, with current husband Jim Toth - revealed her favourite passage from the book, which compared parenthood to an apple.

The quote reads: "It was like training yourself to live on the smell of an apple alone, when what you really wanted was to devour it, to sink your teeth into it and consume it, seeds, core, and all."

For the star, it resonated as her own children are getting older.

She added: "It's such a vivid way to describe the loss of your children as they grow up."

Reese previously admitted becoming a mother at such a young age - she was 23 when she welcomed Ava into the world - completely changed her life.

She explained: "I had to grow up really fast, and figure out what woman I wanted to be for my daughter."

However, she has also insisted having a baby is a lot easier in your twenties than thirties.

She said: "I find that having little kids is more physical and it's just really hard on your body, so I am glad that I had kids kind of young.

"I had one at 23, one at 27 and then again at 37. And oh my god, having a baby at 37 was so much harder. This is just me being real."