today i was petting my dog sky (a husky, possibly mix) and my girlfriend came across what appears to be a fatty cyst, atleast i think it is. she gets them on her dog (a havanese) and her mom describes them as 'extra nails' and this one looks the same on my dog, but he wont let me look at it closely, i guess hes afraid of me hurting him or this spot hurts him. is this what a fatty cyst is? and if so what causes it and what can i do to prevent them/get rid of this one? we got him from a shelter in october, they said he may be somewhere from 1-3 years old and hes a pretty lean dog so i think its a bit young for him to be getting these isnt it?