Tax filing: Newborn Baby Without ITIN and currently not in US

I am a resident alien for tax purposes in US. I was blessed with a new born baby last year and I am looking for the best way forward to add her as a dependent to claim the dependent credit of $500.

https://www.irs.gov/newsroom/understand ... %20numbers.

Currently baby and her mother are out of US on vacation and the baby doesn't have an ITIN. I believe request for new ITIN application (W7) can be sent along with tax returns and W2, but for this should the supporting documents be verified by a certified acceptance agent? Can this be done without the baby being physically present in US?

If its not possible, can I still file my tax returns without adding my new born baby as a dependent and not face any complications with her future stay in US?

Or should I file for a request of tax extension till they are back to apply for ITIN and file taxes together?