Filipino citizenship by birth

[TheGoods]

A child who is 18 years of age or above at the time of the parent’s reacquisition of Philippine citizenship but was born when either parent was still a Filipino citizen, is considered to have been a natural born Filipino and may apply for reacquisition of Philippine citizenship on his/her own behalf. In addition, the applicant must show proof that either or both parents were Filipino citizens at the time of his/her birth.

My question is what proof do I need / or can use to prove that my parents were filipino citizens at the time of my birth and naturalized after?

Thanks for the information

 

[David_L_]

you may show some documents of their naturalization, and compare that date to the date on your birth certificate.