Well, you have to listen to the "experts". My experience has been with Belgians who have been socialized to small children as puppies.
That said, I would never trust any dog around small children. In my opinion, this is a bad mix, because small children just do not understand the differences between a dog and a stuffed animal.
Properly trained, and supervised, a good Belgian would make the adjustment very quickly, because they are very smart, quick to pick up on your desires, and not all that hard to "re-train".
Because they are so smart, they really aren't appropriate dogs for fools, and humans societies are smart to be careful about placement, in my humble opinion.
The reason they worried about this particular Belgian is because her foster human woke up to pee one night and flung the sheets off, and the dog freaked out and bit the crap out of him. They said that the dog had been attack trained and starved for affection, so it wouldn't have second thoughts about biting. Pity.