怎樣用英文祝賀朋友生了BB?

U can say:

Congratulations for having such a lovely baby!



Your baby is so amazingly strong and healthy!



May God be with you and your new born baby forever...



Congratulations on the birth of your healthy and lovely baby!



I'm almost jealous of this baby because of his/her wonderful parents.



It is so nice having a lovely & beautiful baby that definitely is the most amazing, exciting thing in the world.

通常以下幾句:
Congratulations on the birth of your baby girl / boy.
A massive congratulations on the birth of your baby!
Congratulations on your new little angel!
I wish you joy as you share your love with this precious gift from heaven above

希望幫到你