Hi, I think (but not sure) the child is not automatic a british citizen bcoz he/she was born in UK, (it only happens in US if a child is born there its automatic the child is US citizen).

If both parents are are still holding Filipino citizenship when the child was born in UK, the child is still Filipino citizen. But if the parents will have their ILR or permanent residence permit in UK, therefor they can apply the child for British national or something like that

but still read the home office webby