Wilkinson was born in Pointe-Claire, Quebec to parents Keith Wilkinson and Shan Evans. Her Danish-born English father is a former director of the Canada national rugby union team. Her mother was born in Cardiff, Wales. She has a younger brother, David, and a twin sister named Sara. She attended Villa Maria High School in Montreal and was Valedictorian of her class. She played for the Quebec Provincial Team from 1997–99 and was named most valuable player in 1999 after helping the club to the silver medal at the nationals. In 1997 and 1998, she helped Lac St. Louis Lakers earn two silver medals at the national club championships. She was selected as the Greater Montreal Athletic Association's Most Valuable Soccer Player in 2000, and attended the National Training Center Camp for the under-19 Canadian National Team in 2001. Wilkinson competed for the Lakeshore, a female ice hockey team, and also played rugby from 1998–1999.
Wilkinson was named to the 2003 W-League All Star team and the 2004 W-League Championship All Tournament team, She won the W-League 2005 Scoring Championship and tied for the Assist Leader with 38 points on 13 goals and 12 assists.