hi welcome to the forum,
you can check the british embassy manila for the requirements of your daughter to acquired british citizenship. It's a lot of work and expensive but it will be worth everything, but i think you really need to discuss it with your gf, coz if your child become a british citizen, your daughter will not be allowed to stay in the phils for a longer period of time unless she will have dual citizenship. but thats just my opinion, the right thing to do is visit the british embassy website and you can e-mail them your concerns![]()
good luck