Doctors in the UK, the training and the facilities are some of the best in the world. Unfortunately some NHS hospitals have bad reputations, are poorly equipped and have a mix of not so good staff. If you do some searching on google, you can see the scores for hospitals, reviews and see what standards they have against the national benchmark.
Your other option is a private hospital in the UK, and I can assure you that most of the Private hospitals would very much exceed what you'll get from the best hospitals in the Philippines (St Lukes, Manila Doctors Hospital etc). Your treatment would be much less then the cost of going to the Philippines.
As for Great Ormand Street, that is one of the best (if not THE best) childrens hospital in the world with the best facilities money can buy, and the best specialists in the associated fields.
