Brooke Biermann has a secret caddie.

Except this individual doesn’t hoof a bag, get yardages, recommend clubs or read greens. Ashleigh Biermann, two years younger than her sister, is Brooke’s biggest fan and supporter.

“She’s an inspiration to me,” said Brooke, 22, a 2025 Michigan State graduate who will tee it up in the 125th U.S. Women’s Amateur at Bandon Dunes.

Ashleigh was born with Jacobsen syndrome, also known as 11q terminal deletion disorder, a rare chromosomal condition caused by a deletion of genetic material from the long arm of chromosome 11, and specifically at band q24.1. The deletion can lead to a range of developmental and physical conditions. Ashleigh has undergone dozens of surgeries, including an open-heart operation, and until recently couldn’t do everyday functions such as riding a bike or swim.

But ever since big sis burst onto the junior/amateur golf scene – her first USGA championship was the 2019 U.S. Girls’ Junior at SentryWorld in Wisconsin – Ashleigh has been walking the fairways and cheering on her favorite golfer. She was at the 2025 U.S. Women’s Open Presented by Ally at Erin Hills, hobnobbing in Player Dining with the world’s best golfers while loving all the free food.

She attended Brooke’s first collegiate win in 2023 when, as a sophomore, she bested the field at the NCAA regional held at PGA National in Florida, an event the Spartans also won as a team. While she wasn’t at Biermann’s other college victory at Briar’s Creek in South Carolina a year later, Ashleigh was the first to call and congratulate Brooke.

Because of her new job as a pre-school daycare teacher at Woodlawn Chapel in suburban St. Louis, Ashleigh unfortunately could not attend last month’s Women’s Western Amateur in Michigan, where Brooke reached the semifinals for a second time (also in 2022), defeating British Women’s Amateur runner-up and Texas All-American Farah O’Keefe in the Round of 16, 5 and 4, after rallying from a disappointing opening-round 75 just to qualify for match play.

Officials and fellow competitors noticed someone was missing from Brooke’s gallery.

“I have played that tournament like the last six or seven years and everyone wanted to know where she was,” said Brooke. “Every single official was asking, ‘Where’s Ashleigh?’ She’s definitely a staple at these amateur golf events. A lot of players were asking, ‘Where’s your sister?’ She’s so kind and outgoing. She comes up and talks to the [other] girls whether they know her or not. She loves that community.”

Just seeing what Ashleigh has endured since birth has given Brooke much more perspective on life. A bad day on the course doesn’t even compare to what her little sister has overcome. All the surgeries and physical therapy. Just simple tasks like reading or riding a bike took longer for Ashleigh to comprehend.

 She can ride a bike and swim. Ashleigh attended the same public school, Lafayette High in Wildwood, Mo., as Brooke, although she had teachers dedicated to special-needs students. She is able to walk 5-10 miles a day around the neighborhood or nearby parks. The only every-day activity she can’t do is drive.

When Brooke is home, Ashleigh will accompany her to the Country Club of St. Albans for practice sessions. There are days when the mercury reaches 90 and Ashleigh will be out there watching Brooke hit balls or putt for up to six hours. And she rarely misses a tournament.

“She doesn’t have any interest in hitting [a golf ball],” said Brooke. “She just watches me. She’ll take video. I always ask her, ‘Are you enjoying this? It’s so hot. Are you bored?’ She loves it.”

Even though Ashleigh can’t physically play, she lives vicariously through her big sister, and in turn, Brooke is inspired by her courage. Ashleigh also isn’t afraid to be a constructive critic when she doesn’t have a good round or offer praise on good days.

“She is always ready to give me a hug and celebrate,” said Brooke. “She is always positive. She has such belief in me. If I play bad, she’ll say ‘tomorrow you’ll play better.’ She shows me every day how hard she works. She has such a great work ethic.

“It gives me perspective of what is important in life. I’m blessed to be healthy and able to compete at the highest level.”

This will be Biermann’s third and final U.S. Women’s Amateur start. She also qualified for the 2021 U.S. Women’s Amateur Four-Ball at Maridoe Golf Club, in suburban Dallas, with Julia Misemer, a University of Arizona rising senior from Overland Park, Kan. This fall, Biermann, who earned her degree in human resources, will enter LPGA Tour Q-School in what she hopes will be a fruitful professional career.

At Michigan State, she helped the Spartans reach the NCAAs in her final three seasons. Besides the two victories, Biermann compiled a career scoring average of 72.96, the third-best in program history. As a senior she was named an honorable-mention All-American by both the Women's Golf Coaches Association and Golfweek, as well as a Big Ten Distinguished Scholar. Her scoring average in 2024-25 was an impressive 71.91, the fourth-best single year in MSU history. Last summer, she won the Missouri State Women’s Amateur.

In 2023, she received a sponsor’s exemption to play in the Meijer LPGA Classic. At this year’s U.S. Women’s Open, she played a practice round with two-time major champion and former world No. 1 Lilia Vu, and despite an opening-round 80, she responded with a 72 on Day 2 that included a 3-under 33 on her final nine holes.

That performance provided some extra confidence.

“It was an incredible experience there,” she said. “Just to go play with the pros. I told myself if I can do that in Women’s Open conditions, I can do that anywhere, especially in that environment and being around the [world’s] best players.”

Now Biermann hopes to end one final USGA drought: making a cut. She has not made match play in her four previous amateur starts going back to that 2019 U.S. Girls’ Junior. A year ago at Southern Hills, she lost in a playoff for the final spots in the draw.

“I don’t know what it is,” said Biermann, who has made nice match-play runs at both the Women’s Western Amateur and North & South Women’s Amateur at Pinehurst. I love the head-to-head competition of match play.

“But even if I don’t make the cut, I can’t get too mad. The USGA runs such amazing events. I can say, ‘Wow, this has been a great week.’ But I’m focused on making the cut and having a good run.”

And bringing a smile to her biggest fan.

David Shefter is a senior staff writer at the USGA. Email him at dshefter@usga.org.