Greencard Eligibility for newborn child as a dependant

[dkk]

Hi,

 

My Family based "F4 Category - Brothers & Sisters" priority date would become current by the end of 2015. However currently we are expecting a baby in early 2014. My question is will be baby be eligible to come along with me as my dependant ?( I already have inculded my wife as my dependant by sending a mail to the USCIS).

 

How will the process work. Should I send a postal mail/email to the USCIS to add him as my dependant when the my date becomes current or just wait till the interview.

 

And on the other side, will by brother (who is my sponsor) have to take into account the newborn baby while sending the affidavit of support.The current family size is 9 incudling my me, my wife, and my brothers' family. Will he have to show his family size as 10 when he sends the affidavit of support because our chidl would be born by the time our priority date becomes current.

 

Please, please do answer my question and clear my confusion. It all seems to so confusing and complicated to me.

 

Thanks in Advance !!!