She is perhaps best known for her role as the "Star Child", Elizabeth, who is half Human/half Visitor in the 1984 television series V. She also starred in the soap operaGuiding Light as Morgan Richards Nelson from 1981-1983. Cooke played "Debbie" on the critically acclaimed NBC series A Year in The Life. Her only well-known film role is in the 1986 horror film Friday the 13th Part VI: Jason Lives as Megan. Cooke's only guest appearance on TV is on the HBO series The Hitchhiker.
After appearing in Friday the 13th Part VI, Cooke retired from acting, but is active in the Urantia Brotherhood/Fellowship. She has been married to Celestial Seasonings co-founder Mo Siegel since 1989. She briefly returned to the public eye in 2013 when she was interviewed for Crystal Lake Memories, a retrospective documentary about the Friday the 13th film series, in which she recalled her role in Part VI.