It all started way back when, when it was just Turk and J.D.
They are the BEST best friends in hollyweird.
Zach was a groomsmen in Donald's wedding...
...and only besties would know to make the same face at the same time.
Oh, just Zach and Donald singing an adorable duet together:
Christmas music not your thing? Okay, how about them being political together.
If you're going to vote on anything, vote them at BFFs of 2013.
Sorry, are we moving too fast? Let's take a sneaky hug break:
Okay, good. now look at Zach touching Donald's breast area:
It's pretty obvious this isn't just any old friendship...
Have you SEEN Donald's neck tattoo?
Zach showers Donald with gifts:
And knows how to make him happy:
Plus these two can be totally honest with each other.
Still need more proof?! Just look at any one of these photos:
The "two faces become one":
Not only do these two share a tennis racket, but a place in each others heart...