The, "God works in mysterious ways" bullshit answer... Maybe it's some kid born grotesquely handicapted who will die by the time he is 8, you ask why, and some stupid christian answers, "god works in mysterious ways" 
Really? Is that a fucking serious answer? God decided to destroy this kids life for some mysterious reason we're just supposed to have faith in he had a reason for? fuckoff lol... no.... Stop saying that crap...
Maybe they aren't sure what to say and are trying to provide some comfort to the people. I believe that God made everything "good" and the reason anything is "abnormal" or "imperfect" is because sin entered the world. Doesn't seem like it would be accepted more easily if someone said something like "sin works in mysterious ways."
You may see the child as a sad case worthy of your pity that will never have a "normally functioning body" and thus life in your opinion when some people have completely normally functioning bodies and are the most miserable people you've ever met.
While I def. can't purport to know why God allows some suffering I do believe that God makes things for eternity while humans usually see things in a temporal and/or earthly sense. But I guess that could be just another way of saying the same thing you hate to hear
