I think that the following text chunk in bold is wrong:
I have often heard my father caution him against his wild recklessness, but he would only laugh, and say that the tumble that killed him would be from the back of a horse yet unfoaled.
Edgar Rice Burroughs: A Princess of Mars.
But I do not know. The translation to other language from this sentence is like follows:
The horse has not yet been born, from the back of which he will fall and get killed.
I can understand all words in the original sentence, but I can not find this meaning in this sentence.
In a case I am wrong would you like to explain why is original sentence correct and maybe why is it similar to the translation?
I would like to have an explanation why such sentence structure is correct (or incorrect) and how can I learn to understand this sentence structure?