Your must be joking, it's hard enough for Filipina's to bring their sons or daughters here with them. They have to prove that the have sole responsibility for them and that no one else that can care for them or support them if they stay in the Philippines.
Apart from, as others have said, it would be a very bad idea to start your married life in this way, there is absolutely no way she would get a visa, so you should tell your fiancee that ASAP, so she doesn't get her hopes raised on this one.
Iain