Properties for the "last parents" need to be the "last second parent"

[zLinz]

I have some questions with the TreeLayout.
I need to implement kind of this effect:

But what i got in the document was <properties for the “last parents”> i could use.
So i have done like this:

what should i do?
thanks a lot！！！

I just want the last two nodes link like the first pic.

[walter]

Which are the “last two nodes” that you are talking about?

The general answer to your question is that you can override TreeLayout | GoJS API to assign whatever specific TreeVertex properties that you want for any particular Node. But I still do not understand exactly what you want and what you have implemented so far.

[zLinz]

Thank you @walter , sorry for my bad expression. I will check the link you mentioned.