Well, we all know what happens when you assume.

There is no "hostility" in asking a question to answer a question. Tone is important and as I've stated, when said with a smile and a friendly tone, the question fosters a conversation instead of a transaction for personal information.

It's important to establish your image or "brand" in your career and it's equally important to establish boundaries between professional and personal life. Using the question "Why would you like to know?" in a friendly and polite way is a good way to deal with the LPT request.