I've played on the biggest stages, on the biggest tennis courts in the world. I've played on Arthur Ashe Stadium in the US Open finals, Court Philippe Chatrier in the French Open semifinals, Rod Laver Arena in the Australian Open semifinals, Centre Court at Wimbledon. I've been ranked as high as No.7 in the world. 

Those highs, those opportunities are what I put thousands of hours into, what I've sacrificed my childhood for, time with my loving family, time to be there for my younger sisters, who I want nothing more than for them to see me as a role model.  

To walk off the court and be flooded with hateful messages from complete strangers, messages of racial abuse, calling me ugly, wishing violence on me and my family, all because I lost a tennis match? 

It's not ok and it shouldn't be tolerated by anyone, not the social media platforms themselves, not by the social media community at large, and certainly not by me. 

"I have a right to stand up for myself and so does any other person who's subjected to online abuse. We don't have to sit quietly and take it." 

For a long time, I tried to let it go. "Don't draw attention to it, Madison, you're just giving the haters what they want." But then I realized that's just nonsense. I have a right to stand up for myself and so does any other person who's subjected to online abuse. We don't have to sit quietly and take it. 

I think because people don't see someone face-to-face on social media, it's so much easier to just say horrible, hateful things. It's something that obviously athletes and celebrities are dealing with, but it's also something that kids in schools are dealing with. But they don't feel they have the platform to talk about it, to do something about it.

That's why I think suffering in silence just isn't healthy. We need to talk about it. We need to constantly remind everyone that yes, there is a human being on the other end who is reading what you wrote and that it affects them. Your hate doesn't just go into some black hole with no consequences. You're hurting people. 

It has been reported that nearly half of young people have received intimidating, threatening or nasty messages online and that girls are much more likely to be victims of cyberbullying than boys. Strong connections have been made between social media use and mental health struggles, and girls are especially at risk of suicidal thoughts and behaviors.

"There is so much negativity on the internet, and it can be hurtful and damaging. I want to help show the world the power of kindness, and the difference we can make when we take action."

Standing up for myself has definitely made me feel a lot better. You don't always have to comment back, just talking about it is important to raise awareness about just how vile things can get online. 

It's amazing how many people still don't know that it goes on. Whether it's responding back to that person directly or talking to a principal or a parent, raising the awareness about online and real-life abuse and bullying, it needs to be a conversation. It doesn't seem like we've gotten to that point yet. 

That's why I'm excited with FearlesslyGirl to kick off #KinderGirlWorldDay on May 21st. It's an opportunity for all of us to take a meaningful step to fight back against the toxicity of social media by posting about a woman you respect, admire, and want to recognize with a supporting message online.

There is so much negativity on the internet, and it can be hurtful and damaging. I want to help show the world the power of kindness, and the difference we can make when we take action. We start with a day, a day can become two days, two days become a week, a month, and so on. It can start with us.  

Madison Keys is a proud ambassador for FearlesslyGiRL. The organization is asking everyone to join #KinderGirlWorldDay on May 21st and help change the world one day, one post and one girl at a time. Participants are challenged to tag and recognize a fellow girl or woman on social media, and leave them a message of support and kindness, using the hashtag #KinderGirlWorldDay and tagging @fearlesslygirl.