There's a Wheaton Terrier named Vito who lives next door who is a few months older than Niko. They met early on when Niko was a peanut compared to Vito the elephant. Every time Niko goes out the front door, he looks over to see if his friend is outside. They pine for each other and have a blast playing together. Vito and Niko chased each other around in the yard, shared a bowl of water, and a shady spot next to the deck.
The few times that Niko got loose from his leash & collar, Vito was a great aid. Most of the time Niko runs away to look for Niko. We're able to corral Niko back because of Vito.
Here's a "before and after" picture of last summer vs. this weekend: