Is this normal?

I know I gave birth 4 times plus I raised my nephew for most of his young childhood, I should know what's average for achievement and growth milestones. But still, I find myself watching Xander and frequently asking, "Is this normal?"

Yesterday I brought him home for an hour after church, before I had to head off to work. I pulled his boots off and one of his socks stayed inside a boot. I set him down and chased him off to find PaPa - one sock on, one sock off - he was only here for a short while, what did it matter. He got to the living room and decided that this one sock business was just too wierd so he pulled the other one off. Nothing too abnormal about that. Except that he didn't just throw his sock on the floor and climb up on PaPa like I would assume a "normal" child would, he carried it back to the door and tucked it into the boot that didn't have a sock stuck in it. Is this normal? (OCD comes to mind)

Then there is the nativity set. Last year I bought the Fisher Price nativity set for him so I could teach him to leave mine porcelain set alone. I have my set on display exactly at his eye level. There are horses, cows, donkeys and people figurines - not once has he even attempted to touch it. Is this normal?

He played with his FP nativity set last year when he was 10 months old, but I put it away with the Christmas decorations - he hadn't seen it since. I set it up last week. Before Xander had come over to see it, while cleaning the spare room I found a Fisher Price "little people" on the floor. I thought to myself, "This kinda looks like the nativity set." And I brought it out and set it with the wise men.

Cute eh? And he has gifts - I thought it appropriate for the nativity scene.

I set the scene up with the fence off to the left and the wise men and "gift boy" on the right and the animals sort of scattered around. The first time Xander came into the room and saw the nativity set he gathered all the animals and put them inside the fence and took the "gift boy" and threw him across the living room and continued to play with the others. I was shocked! At first I thought maybe we were raising a prejudice child because the "gift boy" was black. But then I realized that one of the wise men figurines also has a black face. How did he know this particular one didn't belong?

Thinking it was a bit of a fluke, after Xander left I set the scene back up again - with the gift boy standing proudly beside the 3 wise men. The next time, after X had been here and left, I found gift boy inside the toy bucket while the rest of the nativity scene was neatly ordered. Is this normal?

Barbee came over one day and I was telling her about my OCD grandson. She purposely set all the animals outside the plastic fence and asked me to video Xander coming in to the room the next time. He was here for about two minutes the next day when I thought, "Oh crap! I forgot to have the camera ready." I went to grab the camera and glanced over at the nativity scene and all the animals were already neatly ordered inside their pen. He hadn't been in the room for 60 seconds. Is this normal?

Tonight Xander and his parents stopped by to bring a plate of cookies they had baked and decorated. After they left here is the scene in my living room:

Animals and wise men neatly ordered. "Gift boy" discarded and laying on the nearby ottoman. Is this normal?

Like, seriously! How does he know this? And why does he care??? He's 21 months old!