Student or Learner
If a person is third son to is father.
how to ask a question so that his answer is
I am" third" son to my father.
Is it right?
What is your birth ordinance?
This question comes up at least once a month.
English does not have an elegant way to ask "how manieth" or "whateth number" so that you hear "third" or "sixteenth" or "twenty-third" instead of 3, 16, or 23.
If you search "what number" or "how manieth" in the search box, you'll see many threads.
You can ask simply "What number child are you in your family?" or "Where do you fall in birth order?" or simply "Do you have any older brothers or sisters?" and the information you get back will answer your question.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.