Before she died, 27-year-old Holly Butcher wrote a letter we all need to read.

Holly Butcher was the picture of health.

The 27-year-old from Grafton, NSW ate all the right foods, hardly drank alcohol and exercised regularly. But that's the thing about cancer, it doesn't discriminate.

On October 31, 2016, her world was turned upside down when she was diagnosed with Ewing sarcoma, a rare but aggressive form of cancer that affects the bones.

Less than 1.5 years later, in the early hours of January 4, 2018, Holly died, surrounded by her loved ones. But it's her poignant open letter, written before her death, that captured the hearts of people around the world.

Cancer forced Holly to face her mortality. She grieved for all the milestones she’d never experience, the kids she’d never get to have, and the future she’d never get to build with the love of her life.

She spent hours reflecting on her life and what really matters in the grand scheme of things. Then, Holly penned an open letter to all of us, which her family shared on her Facebook page after she died. We can't stop thinking about it, even seven years on.

If you read one thing this week, make sure it’s this.

“It’s a strange thing to realise and accept your mortality at 26 years young. It’s just one of those things you ignore. The days tick by and you just expect they will keep on coming, until the unexpected happens,” Holly began.

"I’m 27 now. I don’t want to go. I love my life. I am happy... I owe that to my loved ones. But the control is out of my hands." Image: Facebook/HollyButcher.

"I always imagined myself growing old, wrinkled and grey — most likely caused by the beautiful family (lots of kiddies) I planned on building with the love of my life. I want that so bad it hurts."

That's the thing about life, Holly explained, it's "fragile, precious and unpredictable". Each day is a gift and not a given right.

"I’m 27 now. I don’t want to go. I love my life. I am happy ... I owe that to my loved ones. But the control is out of my hands," Holly wrote.

Holly penned the letter not so we would fear death, but so we could start an honest conversation about it and begin to focus on the important things.

"I just want people to stop worrying so much about the small, meaningless stresses in life and try to remember that we all have the same fate after it all, so do what you can to make your time feel worthy and great, minus the bullsh*t," she explained.

Watch: Professor Richard Scolyer talks about defying his cancer prognosis.

The 27-year-old wanted us to put our problems into perspective whenever we encounter a minor inconvenience in our lives.

"You might have got caught in bad traffic today, or had a bad sleep because your beautiful babies kept you awake, or your hairdresser cut your hair too short. Your new fake nails might have got a chip, your boobs are too small, or you have cellulite on your a**e and your belly is wobbling," she said.

"Let all that sh*t go... I swear you will not be thinking of those things when it is your turn to go. It is all SO insignificant when you look at life as a whole.

"I’m watching my body waste away right before my eyes with nothing I can do about it and all I wish for now is that I could have just one more birthday or Christmas with my family, or just one more day with my partner and dog. Just one more."

Instead of focusing on the negative, Holly urged us to: "Get out there and take a freaking big breath of that fresh Aussie air deep in your lungs, look at how blue the sky is and how green the trees are, it is so beautiful. Think how lucky you are to be able to do just that — breathe."

Holly hoped her reflections could help others. Image: Facebook/HollyButcher.

Lessons to live by.

Holly shared her rules for making the most out of life that she hoped we could implement in our own lives. They're so simple, yet often things we forget about until it's too late.

Here are Holly's lessons to live by:

• Get up early sometimes and listen to the birds while you watch the beautiful colours the sun makes as it rises.

• Listen to music... really listen. Music is therapy. Old is best.

• Cuddle your dog. Far out, I will miss that.

• Talk to your friends. Put down your phone. Are they doing okay?

• Travel if it’s your desire, don’t if it’s not.

• Work to live, don’t live to work.

• Seriously, do what makes your heart feel happy.

• Eat the cake. Zero guilt.

• Say no to things you really don’t want to do.

• Don’t feel pressured to do what other people might think is a fulfilling life ... you might want a mediocre life and that is so okay.

• Tell your loved ones you love them every time you get the chance and love them with everything you have.

• Also, remember if something is making you miserable, you do have the power to change it — in work or love or whatever it may be. Have the guts to change. You don’t know how much time you’ve got on this earth so don’t waste it being miserable. I know that is said all the time but it couldn’t be more true.

Holly finished off her letter by giving us one easy, practical thing most of us can do that will make a huge difference to the lives of people just like her.

"If you can, do a good deed for humanity (and myself) and start regularly donating blood," she said.

"Blood donation (more bags than I could keep up with counting) helped keep me alive for an extra year — a year I will be forever grateful that I got to spend it here on Earth with my family, friends and dog. A year I had some of the greatest times of my life."

Holly said she always imagined herself growing old and grey. Image: Facebook/Holly Butcher.

A lasting legacy.

Holly's words have gone on to reach more people than she ever could have imagined. Seven years on, they're just as powerful as the day she wrote them.

Speaking after her death, Holly's older brother Dean said his family was "immensely proud" of the legacy his sister left behind.

"In her final weeks, I sat at Holly's bedside and asked her if she had any big-picture dreams that she wanted me to work towards on her behalf," he told ABC News.

"She happily replied, 'No. I was going to live a simple life. I didn't have big plans, I just wanted to live happily.' It is therefore incredibly ironic that a woman content with life's simplicities ... has had such a huge impact."

Dean continued: "She left us with a powerful message that has resonated with people from all walks of life and from countries across the world. That will always be her legacy."

To find out how you can donate blood and save three lives — visit the Australian Red Cross Blood Service at www.donateblood.com.au for more information.

This article was published in January 2018 and has been updated.

Feature image: Facebook/HollyButcher.