You should ask the social security office if you need to submit your parents' birth certificates or other documents along with your own birth certificate. You would obtain their birth certificates from the vital records office in the state where they were born.
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Here is the website for "How to get or replace anToronto/Ontario birth certificate"
I found the following information on familysearch.org. family search is a free site you just need to register.
Parents marriage certificate
1940 U.S. census states that Patricia Ash born in Ohio
1930 U. S. census states that your father was born in Massachusetts
Dear Ms. Larkin,
Thank you for posting your request on History Hub!
If your parents notified the US Consulate of your birth, there should be a Consular Report of Birth Abroad (CRBA) record for you. Please see the Bureau of Consular Affairs page on How to Replace or Amend a Consular Report of Birth Abroad (CRBA). If there is no CRBA on file for you, the Bureau of Consular Affairs may be able to advise you on what steps to take. See also the US Citizenship and Immigration Service Pamphlet on How do I get proof of my U.S. citizenship?
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