kits and brain damage

Question
i have a strange question for you that im about to try and research which is something im not very good at. ill start from the beginning lol
in Twisty's litter she had a runt that was "dead" as in cold and not breathing, she was like that for no more than 10 mins when i found her and got her going again. the next morning i went out and she was almost "dead" again and once again i fixed her. then when the babies were 4 days old Twisty thought it would be an awesome idea to take her babies outside to live in her monke hammock, when i got home the runt (Brigette) and another one had fallen through the cage about 15cm and were cold and not too good. i fixed them.
anyway, today when i was checking them all out, compairing Brigette's growth to the others (shes growing well by the way) i noticed that Brigette's head shakes alot, not like they nod up and down looking for food, but shaking like sideways a little, just her head. do you know anything about ferrets getting brain damage because theyve "died"? apart from the head shaking shes feeding well and growing and talking but im trying to find out more.
i have been breeding ferrets for years and know quite alot, though i have never come across this problem before.

Answer
I can only offer a suggestion and that is that it is possible for them to have brain damage.  In humans, we only have to be without oxygen to the brain for 3 minutes to experience brain damage.  I would take her to your vet to be sure and to discuss the extent of the damage.