There's a quest that handles this but I cannot remember what it's called from the top of my head. If you search for the "restedWell" perk in the object window, right click on it, click "use info" then in the list that pops up double click on the only quest. Then when you're in that window go to the scripts tab and you'll find the script that handles what rested-type perk gets given in what situation. You'll need to edit this script
- Hypno