Forster comes from a hockey playing family. Her father, Marcel, played in the National League B (NLB) throughout the 1980s and served as assistant coach to HC Ajoie during 2011 to 2015. Her two younger siblings play ice hockey in Swiss leagues – Gaëtan (born 1997) in the 2. Liga of the Regio League and Justine (born 2001) in the Swiss Women's Hockey League B (SWHL B).[3]