Hi, congratulations on the birth of your child and receipt of your PER. So, your file is on its way to AVO and you will need to immediately inform AVO of the birth of your child. You can do this via CSE, https://secure.cic.gc.ca/enquiries-renseignements/case-cas-eng.aspx?mission=accra
Attach the scan of the birth certificate to the CSE and await further instructions from AVO.
In the meantime, begin to process the child's international passport and arrange a new POF for your family which will include your child. Also prepare the FSW application fee for the child.
Wish you the best ahead, cheers.