Pregnancy comes with many things to feel anxious about — even if you aren’t considered “high risk.” Not least of all is worry about how welcoming a new 𝚋𝚊𝚋𝚢 will change your family. Serena Williams opened up about one of the biggest concerns she had when pregnant with 𝚋𝚊𝚋𝚢 Adira, now 1, and it’s something many parents can relate to.

The 23-time Grand Slam champion took to Instagram to reflect on her pregnancy this week with her youngest daughter. She shared whimsical never-before-seen photos surrounded by flowers, where she is glowing in a sheer pink dress that showed her growing bump. Her oldest daughter Olympia, now 6, sits by her in the photos, looking adorable in a pink dress. They both seem so happy and excited to welcome a new little one into the family, but in her caption, Williams got vulnerable about one of her fears.

“Olympia is always there for me,” the Olympic gold medalist wrote. “Before having a second child, I always wondered, ‘how could I love anything as much as I love @olympiaohanian?’” Oh, I have been there! I remember bawling my eyes out on the phone with a friend as my due date approached for my second-born child. I was so worried that I wouldn’t love my second 𝚋𝚊𝚋𝚢 as much, that I would neglect my first child because I was so focused on my newborn, that everything would change for the worst. It’s unknown and overwhelming and scary! My friend, who had two kids at the time, assured me that everything would be OK. Now, 5 and a half years later, I can say for a fact that these two (and their younger brother!) are best friends.

The same thing happened for Williams. “Then Adira came along … she is so special, so fun, so funny, so loving, so sweet and so strong!!!” Williams continued in her caption. “You see, God makes your heart get bigger. Because my love for Olympia has not dimmed. My heart simply now is doubled the size and I have a greater capacity to love more!”

It doesn’t make sense, but I completely understand how she feels. It definitely seems like your heart grows as a mom — and it just keeps growing each year along with your 𝚋𝚊𝚋𝚢.

The Wyn Beauty founder has been sharing tons of professional photos from her maternity shoots this week, and they are all stunning. She posed suspended in the air with aerial silks and even took family photos with Olympia and her husband Alexis Ohanian.

“A year ago today – August 15th – I gave birth to my second 𝚋𝚊𝚋𝚢 girl, Adira River Ohanian,” she captioned one Instagram post. “She is a true light. Here’s a peek inside my maternity shoot. @adiraohanian”

In another, Williams revealed the meaning behind Adira’s name. “Adira is a girl’s name of Hebrew origin and means ‘mighty,’ ‘strong,’ and ‘majestic.’ The elegant name is popular in many cultures around the world. Adira is the feminine form of the classic name Adir. It is a Biblical name, meaning ‘Strong One.’”

Adira is still little, but considering how they already love holding hands and wearing matching pink, we already know they are going to grow up to be besties!