Crying wolf

Sensi is a fearful dog; something that has created a lot of issues for Brent and I over the years.
The lighter side of his fearful temperament is watching him get scared of the most mundane things — a large rock, a tree branch swaying in the wind, a paper bag laying on the floor.
We laugh and coax him into sniffing the items, getting him to realize it’s nothing to be scared of.
When he goes outside to go potty, he’ll bark if the wind howls or blows leaves around. It seems like he’s always finding something that he’s scared of.
For Brent and I, it’s like he’s crying wolf.
Of course, we know he really is scared, but we also know that he gets scared when there’s nothing to worry about.
Generally, we write off his fearful barks as meaningless.
Which begs the question, how do we know when they’re not?
This morning, I let Sensi out to go potty as usual. Not surprisingly, he started barking after just a few minutes of being outside.
I let it go for a second, and then opened the door and leaned out.
“Sensi!” I scolded. “Shhhhh!”
He paid no attention to me and instead trotted forward in the direction he was barking, toward the side of the house.
I closed the door, in too much of a hurry to go get him and bring him back in.
As I finished making my lunch, he was still barking. I went back to the door and this time, he was standing on the porch but still facing and barking in the same direction.
I let him in, and instead of joyfully running toward his food dish, he cautiously walked inside and to the back of the living room to look out the doorwall in same direction he had been barking.
Odd, I thought.
I put food in his dish and called him. He ate a few morsels and walked back to the doorwall. A couple seconds later, he walked back in the kitchen and looked up at me.
“Arrrr-woof,” he barked quietly. It was very odd.
He finished his breakfast and immediately went back to the doorwall, staring outside.
Before I left, I looked in the direction he was staring but didn’t see anything. I wrote it off as nothing — perhaps he saw a deer or a dog or some other animal.
But as I walked to the truck, I couldn’t help myself from wondering, what if he wasn’t crying wolf?
And if he wasn’t, what the heck did he see on the side of our house?