Why doesn't a definitionMessage have a parent?

[kharybdys]

I had code that tried to go "up the tree" from a property to find the complete path to said property, but which stopped at the definitionMessage as said message didn't have a parent. I currently fixed it by not going up, but going down and passing the partial path, but maybe a definitionMessage should have a parent.
Note that if we implement this, we run the risk of unintended consequences as other code might depend on them not having a parent.