If you mean someone that was your friend, you UNfriened them, and now you just want to re-add or re-friend them? Then YES, why not? as long as they didnt block you.
If that is not what you were asking then please clarify.
it sounds like he might have blocked you...
When you find him through Likes common with your cousin, are you able to click his picture, or does it have an unclickable grey-man-shadow picture? If so, you're blocked.
Sounds like he's got his profile locked down to everyone or maybe just you.. In this case, you will only be able to do (from your account) the options shown on the page.. If there is no add-button, then you can't add him.. Period.
Best to try and contact him outside of Facebook or via another account.
Are you able to click-to and view his profile page? If not, you are blocked. If this is the case the only thing you can do is ask him to unblock you..
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