puppies and kittens

hello everyone:)
   
i saw this video on youtube awhile ago.. i was just wondering, are the kittens and puppies afraid of each other?
   
if so, how come?
   
i was thinking that maybe it's because they aren't acquainted with each other..
   
but the puppies and kittens are all so cute and adorable!!:D
   
also, the kittens seem to be having fun playing with the balls:P
   
here, have a look at the video:
   
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