John-

I built this dutch door from 2X6 western red cedar with drawbored M&T
joints.

https://www.dropbox.com/s/vtfrl8e4cw0avn6/Door.jpg?dl=0

Some of the drawbore pins can be seen.  It's held up well with no sag.  Not
readily apparent from the picture is that the joint is a double M&T like
this-

https://www.woodworkingarchive.biz/machine-cut-joint/images/1369_55_264
-double-mortise-and-tenon.jpg">https://www.woodworkingarchive.biz/machine-cut-
joint/images/1369_55_264-double-mortise-and-tenon.jpg

to avoid wide and more unstable mortise cheeks.

Phil