His home course in Lakewood, Washington -- Tacoma Country & Golf Club -- was where the Putnam brothers (Andrew and Michael) honed their games growing up in Tacoma, Washington before they reached the PGA TOUR.

Frequently had chipping contests at Tacoma Country & Golf Club with RJ Manke, who later played the 2023 Korn Ferry Tour season with Highsmith. The two were also teammates in high school (Bellarmine Preparatory School) and at Pepperdine University. As kids, they frequently spent all day at the golf club with their older brothers. These days, if they are all together at Tacoma Country & Golf Club, they will play a round of golf and follow it with a pickleball match.

Played piano for 12 years.

Once claimed he was better at pickleball than golf.

Maintains a friendship with 15-time PGA TOUR winner Fred Couples, who also hails from the state of Washington. The two have mutual friends and first met at the 2017 Junior Presidents Cup, with Couples serving as an assistant captain for the 2017 Presidents Cup.

Favorite athletes include professional tennis players Gael Monfils, Nick Kyrgios, and Dustin Brown.

Finished No. 10 in the Class of 2022 PGA TOUR University Ranking, earning PGA TOUR Canada membership for the remainder of the 2022 season and an exemption to Second Stage of the 2022 Korn Ferry Tour Qualifying Tournament.

Played four seasons at Pepperdine University (2018-22), earning three All-West Coast Conference First Team selections (2019, 2021, 2022), the 2019 WCC Freshman of the Year award, and three individual victories.

Posted a 3-0 record in match play as he helped Pepperdine win the team national title at the 2021 NCAA Championship; he defeated Florida State's Cole Anderson in the quarterfinals, Oklahoma State's Aman Gupta in the semifinals, and Oklahoma's Garett Reband in the final.

Qualified for the 2021 U.S. Open (missed cut) between his junior and senior seasons at Pepperdine.

Qualified for four consecutive U.S. Amateur Championships from 2018 through 2021, advancing to the second round of match play in 2021.

Advanced to the quarterfinals of the 2018 U.S. Junior Amateur Championship contested at Baltusrol Golf Club; he notably defeated second-seeded Ricky Castillo in the Round of 16 before he fell to Michael Thorbjornsen in the quarterfinals.

Captured the 2017 Washington State Amateur in August, posting a second-round 65 to go with his opening and closing 70s to defeat Derek Bayley by two strokes at Tumble Creek Club in Cle Elum, Washington.

Helped the United States win the 2017 Junior Presidents Cup under captain David Toms and honorary captain Jack Nicklaus.

Selected to the AJGA Rolex Junior All-America First Team in 2017.