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					Originally Posted by  Yodi     Hi 
Mardelin  Can a yorkie age 4 months come in to heat??? My little girl has been humpping her pillow alot. 
And licking her privates alot      |  
 
  I've not heard of it, but I suppose it could happen. 
Remember lil girls do hump and are very clean with themselves, so the constant licking could be the result of that.  Check her urn, make sure there is no discoloration in it.  If it is licking to the point of being overly done....maybe you should have her checked by vet....possibility of an infection of some sort.