How do I unblock a person on Facebook?

[tallcrow232]

I had one person listed as my mother on Facebook, then tried to add someone else as a mother. The resulting paradox of two mothers seems to have short-circuited my account, and now the person I tried to add is invisible to me. She doesn't show up on the search bar, and none of my friend's contact lists, but I know her account is still active, just not visible to mine. Has this happened to anyone else, and is there a way to fix it?