Will the mother bird reject the egg if you touch it?
Absolutely not! The old wives tale states that if you touch a
baby bird, an egg or even a nest that the mother bird will stop
feeding the chick, kick the egg out of the nest or abandon the
nest. This is a myth, and is completely false.
That doesn't mean that there isn't some bird out there who's done
it before, or even that a human witnessed it, but it's a safe bet
that the reasons it may have been done were other factors. Most
baby birds in the wild smell worse than your grubby little fingers,
so don't worry about that.
I do not recommend going out and touching birds and nests or eggs
for sport now since it won't affect the feeding of the chick, it is
wise to let them be. Some mothers will peck at you or attack you if
you get too close to their nest. So unless the baby bird is in
danger or potential danger, such as falling out of a tree on the
side of the road or something, leave them be! But don't ground
Johnny for a week because he came home and told you (mom) that he
touched a baby bird! Be happy he's curious about nature and not
playing video games!!