Serena Williams is being transparent about how she feels.

On Tuesday, the 23-Grand Slam champion took to X (formally known as Twitter) to describe how she was feeling, as reported by PEOPLE. In her post, the mom of two had a simple message that some people might resonate with.

"I am not ok today," she tweeted. "And that’s ok to not be ok."

She continued, "No one is ok every single day. If you are not ok today I’m with you. There’s always tomorrow 😘 Love you."

This is not the first time the athlete has used her voice to spread mental health awareness. Last year, she opened up on her wellness journey during a discussion with singer Selena Gomez, for her Wondermind platform.

"Mental fitness for me is just really learn[ing] to shut down," Williams said. "And you know I did this years ago, before even mental health was a topic among everyone's mind."

She added, "It was more just like, alright, I'm shutting myself down today. Just subconsciously, it was something I've always done. And so now that I know that it's so important to just put yourself first, especially mentally, I always have shut down moments. I have serious boundaries and I don't let anyone cross those boundaries."

In August, the athlete welcomed her second child, Adira River, with her husband, Alexis Ohanian. They are also parents to a 5-year-old daughter named Olympia.

Following Olympia's birth –which required an emergency cesarean section– Williams told TIME   how she coped after that harrowing moment. "Some days, I cry," she explained. " I’m really sad. I’ve had meltdowns.”

That same year, she revealed to Harper's Bazaar that she struggled with postpartum depression.

“Honestly, sometimes I still think I have to deal with it,” she said. “I think people need to talk about it more because it’s almost like the fourth trimester, it’s part of the pregnancy.”