Generally the parent owns all property that belongs to the minor or at the least holds them in trust for the minor.
This is just my opinion and not a comprehensive answer. You assume the risk because this answer may not apply to your situation depending on the facts.
Once you turn 18, you should be given possession of those documents by your mother. If not, it is easy to get a new birth certificate from the county in which you were born. As far as the passport goes, you need to contact the passport agency and ask them what you should do. Maybe they will just issue a new one. Check with them directly.
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