When Aaron takes his annual leave to spend time with Jack, he winds up needing Spencer to help him through a hard time.  After the scare is over, Aaron and Spencer find themselves closer than before.

http://geekystudmuffin.livejournal.com/18022.html

Aaron overhears what Emily asks Spencer, and has a question of his own. (First chapter is at the bottom.)

http://geekystudmuffin.livejournal.com/tag/universe%3A%20fathers%20are%20not%20born

In a series of complex cases and life moments, Agents Aaron Hotchner and Spencer Reid pursue criminal minds without losing their own while dating and keeping up their family.

http://archiveofourown.org/series/11189

"So," Reid says, eyeing Hotch warily, "I'm going to leave you here to freak out as you slowly realize that we've been dating for awhile and you just didn't know it."

http://travelinthedark.livejournal.com/10248.html

Aaron doesn't know who he's supposed to be anymore.

http://travelinthedark.livejournal.com/4956.html#cutid1

Aaron's world is a mess, and it falls apart more everytime he tries to fix it.

http://travelinthedark.livejournal.com/2075.html#cutid1

The exchanging of favors leads to love.

http://ice-ziggee.livejournal.com/36303.html

Who in their right mind would ask Spencer Reid to babysit?

http://writing2death.livejournal.com/15670.html?view=126518#t126518