To all of you who replied to my post abt lost Citizenship Certification, thank you for enlightening us about passport being a valid USC proof... so...

now we are planning to not wait for the Copy of his citizenship anymore and just use the passport as proof of his USC.. In the I-129F form, Part A. number 10 or 12? "My citizenship was acquired through...." -- he will check of course PARENTS -- but there is a follow up question with that in the form under Parents, "if Yes, give certificate number"

How can he give the number? he does not have it coz he lost it right? is it ok to leave that blank?

HELP please