• O’Brien was awarded United States High School All-USA Hockey Player of the Year honors and was named to the USHS All-USA Hockey First Team after averaging 2.67 points per game with Thayer Academy in 2017-18 (43-37—80 in 30 GP).

• His head coach at Thayer Academy is Tony Amonte, who appeared in 1,174 career NHL games and represented the United States at the 1998 and 2002 Olympic Winter Games.

• Has committed to Providence College for the 2018-19 season.

• Models his style of play after Blackhawks forward Jonathan Toews.