I didn't read any of the other replies yet, but my Tatum has an open fontanel. It's quite large and I was so scared that she was going to hit her head as that can be very serious and can even cause death if they hit on that spot. I asked my vet about it and he said to just watch her, that sometimes they close on their own and sometimes they never do. She still has it and she will be 2 years old at the end of next month. Tatum was "the runt" of the litter and this very often happens with the tiny ones, so I am assuming that this is why she has it.
The hole you are referring to doesn't sound like an Open Fontanel to me though because of the location that it's in. I honestly have no idea what this could be
but I do hope she's ok!
