Thomson, Heather (Keller) passed away peacefully on November 7, 2017, after a 2-year battle with breast cancer. She was born in Burlington VT on April 29, 1980, to Robin (Kline) and Emory Keller. She graduated from Mount Mansfield Union High School in 1998. She received a double major in mathematics and biology from Wellesley College, graduating in 2002. Shortly after graduating she met her husband Ty Thomson at MIT, and they were married on August 18, 2007. Heather took great pride in her career in early-stage drug discovery working at Archemix and X-Chem, but her family and 3 beautiful children, Kobe, Loic, and Gwenevere, were the true center of her life. She will be missed dearly by her parents, her sister and brother-in-law Amanda and Todd Rea and their children Lucy and Cooper, her father-in-law and mother-in-law Bruce and Chiquita Thomson, her brother-in-law and sister-in-law Garret and Wei-Chien Thomson, and many others whose life she touched over the years. Visiting hours will be held at the Keefe Funeral Home, 5 Chestnut St., Arlington, Saturday November 18 from 3-6PM. A celebration of Heather's life will be held at the Wellesley College Club, 727 Washington St., Wellesley, on Sunday November 19 from 10AM-1PM. In lieu of flowers, donations can be made to the Jimmy Fund or to Cradles to Crayons.