You will have to sponsor your new child for PR once the baby is born. In order to sponsor the baby for PR, either you or your wife must be in Canada and you must remain in Canada while the application is being processed. You can try applying for a TRV so that all of you can travel to Canada together and apply for PR once all of you arrive. If the TRV is not approved then you can try applying for a TRP. If the TRP is also refused, then one of you will have to travel to Canada ahead of the rest of the family to submit the PR application from there and wait out the processing of the application from within Canada.