Are you interested in birds and curious about baby pigeons?

One possibility is that you have seen a baby pigeon, but you just do not know it. Baby pigeons get milk from both their mothers and their fathers; therefore, they tend to grow very large very early on in life. Therefore, you might have seen a baby pigeon flying around, but you just did not notice since they look so much like their parents.
When parent pigeons have babies, they only have two. There are not a handful of crying babies to feed, so the parents get to give the other little ones some extra food.
Most baby pigeons are not permitted out of their nests until they reach maturity. Of course, we can be pretty sure that one of them escapes from time to time. In any case though, most of them are in their nests as babies, so unless you get up close and personal with a pigeon nest, you will never see the baby pigeons.
When you see pigeons, do you notice that many of them come flying out of corners of a building or out from under a bridge? Well, that is because that is where their nests are. The babies are hidden away from sight most of the time. You do not get to see them, because the parents keep them in these discreet places.
Do you really see any baby bird that frequently? Mother birds, in particular, are very protective of their young. Additionally, the babies cannot fly right away, so they cannot escape from their nest. Therefore, you can see why you do not frequently see any baby pigeons.