Proof of relationship with my sister turned cousin

[manavbhanot]

Hello Experts,

I am in process of submitting my express entry profile for immigration to Canada. My younger real sister immigrated to canada couple of years ago. However, due to some family reasons, my uncle adopted my when I was 12 years old and because of that my passport has my uncle's and aunt's name as my parents. Can I display my birth certificate as a proof to establish my relationship to my sister ?