For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
GodsChild Forever
There are so many reasons for God to allow suffering in the life of His children. He is a loving God who is more concerned about our Eternal State and soul wellness much more than temporal benefits of this world, which would anyway vanish. This world and this mortal body are not going to last forever. Suffering and pain are sometimes God's way of bringing us to the right track. Suffering makes us more like Christ and more ready for Christ's return.
http://www.saviorgod.com/p/why-does-god-allow-pain.html