Andie Mitchell is Your Boston Mum.Anthony Migliorino Andie Mitchell is a longtime blogger, author, and recipe developer, best-known for the memoir “It Was Me All Along,” in which she chronicled her evolution from overweight child toward a more measured adult relationship with body image. But, these days, the Norfolk mom of two is better known as “Your Boston Mum,” a social media persona she fittingly created on St. Patrick’s Day, on a whim.