The Legend of the Donkey's Cross - Jesus rode into Jerusalem on the back of a small donkey. The little animal loved him so much that when he was sentenced to be crucified, it wanted to help him bear the burden of the cross. The donkey was driven away but returned to pay its respects when everyone else had gone. As it turned away sadly, the shadow of the cross fell over its shoulders. The mark has remained there ever since as a permanent tribute to the donkey's love and loyalty.
Looks to me like this one's about to go on a "donkey walkabout" as I call them. My Chloe learned from my departed Nutmeg how to watch humans work locks on gates, etc. and then open them herself. I now have to use donkey-proof closures always. LOL.