I had this problem with baby wolves. The baby starts barking non-stop (and baby wolves' bark sound like a cat coughing up a hairball). The wolf it barks at is usually its mother but the mother totally ignores it. I tried picking it up and placing it down but it goes right back at it. Moving the wolf it's barking at seems to work better, but not always.
It also happens with the baby fennecs. And their bark is SO annoying when it goes on for a long time, especially if several babies do it at the same time.