From the info in your posts I assume your mother's maiden name was Mary Jane Dow - she married ?, had 2 children and then married 2nd your father Frank Carlson. I have a book on Dow's, but it is dated 1929, so if your mother was born after that, she would not be in the book. If she was born before that, her birth might be recorded, but with no idea of her parents given names or a date, would be impossible to find in a 1000 pg. book. Can sometimes find a person by spouse name, but don't have name of her first husband - and unless the marriage took place before 1929, it also would not be recorded in the book.
Other Dow names, e.g. your Dow grandparents - and approximate dates of birth are necessary to locate the family in the book.