1. Olive, much like his parents, was painfully shy as a foal. Quite often he would find himself confronted with social interaction (he’s about 6 years old here, and he’s huge compared to the other foals; most think he’s 14 or something and ask him questions he couldn’t answer), and to avoid it, he would hide under his mother’s wing. Really, he’d hide under there for any reason. Only thing is, he doesn’t exactly fit very well. The only thing that’s usually covered is the top of his head.
2. Here’s the difference between and average sized pegasus foal (Cherry Bomb) and Olive. As you can see, Olive is much, much bigger, and his wings are too small compared to his size. They seemed to grow at the normal size rate for an average pegasus, not a half-Clydesdale foal.
3. Troubleshoes was a bit older than Fluttershy at the time they met. While she was about 23 or 24, he was 31 and never really expected to actually have foals, despite wanting them. But when he and Fluttershy found they were expecting, he was thrilled… as well as rightfully concerned for the size of his foal.
Olive Laurel was born overdue, and much to Troubleshoes’ worry, Fluttershy had insisted to birth him unassisted and at home. Basically, he was terrified that something would happen. It showed, too, and he was kicked out of the room to not stress his wife with his constant fretting. But, eventually, he was allowed into the home by Applejack (who simply was there for moral support, and in case something happened). When he first laid eyes on his son (who, as expected, was much larger than the average foal), he knew that this was the best thing in the whole world. His son and wife.
Troubleshoes and Fluttershy go on to have four kids, and thankfully, the rest weren’t too much of a problem.