If you send someone a message on Facebook?

[Taylor]

So I just realized that you have to be friends with someone on FB in order to message them (for it to be sent to there actually inbox not "the other" box) If i sent someone a friend request but have already sent them a message bfor being friends will it notify them after they accept my friend request or will i need to send the same message twice. Thanks!!!!

[Danial]

if you want to you can send twice other wise it will appear in the conversation on its own when one of you would message eachother.

[pri✍]

Message sent to a non friend as you know will be put to the Other folder under the Message; it's a message nontheless, and it will move to Inbox folder after the recipient answer it.

Now sorry, I don't know exactly the answer to your question, whether the pm in Other folder automatically moved to Inbox folder after you become friends.
Why don't you asked that person to find out exactly? Then tell me.... it needs the exact timing to find out this thing you know.

However, if you sent again, for sure that friend will get two of that same message in his Inbox.

[OnlineBiz]

Either you have to be friends with that person or you should have a lot of connections.