This is what it shows on the GC Website.
If a family member is added to an application during processing
During processing, a principal applicant can add a new family member as a dependant, such as a newborn child or, in the case of a parent or grandparent, a new partner. Or, they may request that a family member originally declared as non-accompanying be included as accompanying.
When a family member added to the application is a dependent child of the sponsor, it is not necessary to re-assess the sponsor’s ability to meet the minimum necessary income (MNI). Under R133(4), a sponsor is exempt from meeting MNI requirements for such family members. Applicable fees must be paid, and the new applicant must pass medical and background checks.
If an applicant has a child after they have been issued a permanent resident visa but before becoming a permanent resident, the processing office can:
- add the child to the sponsorship
- collect the applicable processing fee for the child
- issue instructions for the medical examination to the additional dependant
Also, we were approved under AIP and our medical will expire Jan 2020.
That is for Family Class sponsorship, not economic immigration streams.