The younger sister of Katie Summerhayes, Molly started skiing when she was just four at the Sheffield Ski Village. Inspired by her sister, she progressed quickly and was selected for the GB park and Pipe team.
Both a slopestyle and halfpipe skier, she decided to specialise in the latter, picking up gold at the 2015 Junior World Championships in Valmalenco, Italy.
An 11th place finish at the 2015 World Championships in Austria followed, before Summerhayes' progress was stunted by rupturing a ligament in her right knee in January 2016.
But she returned to fitness to qualify for her maiden Olympic Winter Games in PyeongChang, where she claimed a 17th place finish, narrowly missing out on qualifying for the final.