Birth Name: Alyson Lee Hannigan
Place of Birth: Washington, D.C., U.S.
Date of Birth: March 24, 1974
*Ashkenazi Jewish (mother)
Alyson Hannigan is an American actress and television presenter. She is known for playing Michelle in the American Pie films, and for her leading roles in the shows Buffy the Vampire Slayer and How I Met Your Mother.
She has Irish ancestry on her father’s side. Her mother is Jewish (her family was from Poland and Russia). Alyson is married to actor Alexis Denisof, with whom she has two children.
Alyson’s maternal grandfather was Jacob R. “Jack” Posner (the son of Samuel Posner and Goldie Grossfeld). Jacob was born in Maryland, to Jewish emigrants from Eastern Europe, either Russia or Poland, depending on the census.
Alyson’s maternal grandmother is Dorothy Mendel (the daughter of Hyman Noah “Herman” Mendel and Esther Pessie Freedman). Dorothy was born in Atlanta, to Russian Jewish parents.
Sources: Genealogy of Alyson Hannigan (focusing on her mother’s side) – https://www.geni.com
Obituary of Alyson’s maternal grandfather, Jacob R. “Jack” Posner – http://articles.baltimoresun.com
Alyson’s maternal grandmother, Dorothy Mendel, on the 1930 U.S. Census – https://familysearch.org