Chris, if you're still looking for this, you are probably looking in vain. Washington State birth certificates began in July 1907. County births (and there were 39 counties to look in) may or may not have been recorded (there was a less than 50% chance) before that. If you do not find Lucy in the 1900 census, you probably never will find an original filing of her birth. However, if she lived long enough to register for Social Security, there may be a delayed filing. Begin looking for substitute sources to give a place of birth, such as school records, marriage questionnaires, border crossings, immigration records, Canadian alien registrations, the 1911 British Columbia census, and so on.