Apply for Tier2 with newborn baby with no passport

[Flid]

Hello!
My situation: we are here with my wife on Tier 2 (General) visa.
We have a 4-month boy, born in UK, we have a full birth certificate, but still haven't made a passport of our original country.

In theory, I'm going to switch my employer soon, so I need to apply for a visa again. Does my son need a passport for that, of birth certificate is enough?

Sorry if it's already discussed, spent 2 hours trying to find an answer

Thank you!

[VirtualWaver]

I might be wrong but I believe that in order to apply for a visa your baby has to have a passport first. However, as your baby born here, you are not required to apply for a visa for them unless you are planning to travel with them. You can include your child in your next visa extension as long as they will receive the passport. I did that way and they requested my daughter's passport when I included her as my dependant in my extension.

[iworker]

You can apply for the visa without a passport.
You only need to apply the visa for the kid if you are planning to travel.
U do not have to apply for the visa at the same time as you do for yourself. i.e., you can apply later for the kid on its own.

[Flid]

Hi iworker, thank for your reply!
I still want to apply for a visa for my child, as we have a plan to travel in future. And I want to do that in one go, because 1) I want to reduce number of work and 2) company pays for everything now, not sure if it will later.
Can you please put a bit more details on your message?

You can apply for the visa without a passport.

What do I need for that? Just bring birth certificate for my son, and nothing else?