What are the requirements and process for obtaining a dependant visa in Thailand for my newborn?

Thanks for the add.

I need some help with a dependant visa.

What documents ect i need.

The process and cost and any agent recommendations.

Ive a two week old baby here in L.O.S.

My partner is thai, we are not married and my name is on birth certificate.

I have been here 2 years , with my partner all of that time.

I have been bouncing borders on tourist visa since i arrived, now its becoming a problem, im getting 100 questions at the passport control.

I can get an ext on my visa in 10 days but need to sort a proper visa before that expires begining of march.

Thanks in advance for any help

Please no stupid comments.

Looking for genuine help and advice