The marriage was not a happy one. Orford blamed Ellen for the birth of their Squib son, and Dolores came to loathe her mother not only for her Muggle heritage but also her flightiness and untidiness.
When Dolores was fifteen, the tension between Ellen and Orford came to a head and the pair separated. While her ex-husband and daughter continued to live in the wizarding world, Ellen and her son returned to the Muggle world. Ellen would never see her daughter again.
- Pottermore (First mentioned)