Lindsay Arnold is celebrating her first Mother’s Day as a mom with her 6-month-old daughter Sage Jill
Lindsay Arnold baby
Credit: Lindsay Arnold/Instagram

Lindsay Arnold is overwhelmed with the joy of being a mom to 6-month-old daughter Sage Jill.

Arnold, 27, opened up about the "fulfilling" aspects of motherhood in a candid chat ahead of celebrating her first Mother's Day as a mom.

"I am a mom, and it is the best thing that has truly ever happened to me," the Dancing with the Stars alum told Entertainment Tonight. "It's the most fulfilling thing that I've ever had in my life, and I'm just so grateful for the opportunity to be Sage's mom."

She added, "Every single day, I wake up, I'm like, 'No, this is not my life. This is so amazing!' "

Arnold told the outlet that her "whole entire life has changed" since motherhood, but in the "most incredible way."

Lindsay Arnold baby
Credit: Lindsay Arnold/Instagram

The professional dancer – who shares Sage with her husband Sam Cusick – is looking forward to a "nice, fun day" for Mother's Day.

"Literally, I kind of just realized now that this is going to be my first Mother's Day with the baby girl. That is actually crazy," she told ET, adding, "I'm definitely going to have to tell my husband to make sure he gives us a nice, fun day. I guess Sage can't really give me any presents, but truly just her existence is the greatest gift of all."

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Amid all the joys of motherhood, Arnold has also dealt with outside pressure when it comes to how she should parent her daughter, she told PEOPLE last month.  

"I try to focus on the fact that there must be so many moms out there that are feeling these same pressures," Arnold said. "And if I can be open and vulnerable about it, maybe I can help other moms who are feeling the same way, and understand that it's okay and that none of us are perfect. There are trials when you're a mother."

Lindsay Arnold baby
Credit: Lindsay Arnold/Instagram

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The first-time mom added, "There's things that you're still learning and trying to grow every single day and you're not alone. That's kind of what drives me. And at the end of the day, I try to focus and remember that I know what's best for me and my family."