A Google Web Search Help thread has an annoyed searcher who is upset Google's search box offers search suggestions for "youpron" when you type in the word "you."
The easy solution is to turn off search suggestions in your search preferences:
But you cannot turn off search suggestions on every computer your child has access to. So the big question is, should Google's search suggestions have a strong adult filter that disallows adult oriented suggestions by default?
Forum discussion at Google Web Search Help.