i have a question on doves

diz dove laid 2 eggs and one of them hatched they baby dove was about 3 weeks old i juz checked and its not there but da unhachted egg is there. i saw the parents sitting on my fence so can he fly away with them or was he toooo small

 

At three weeks old the baby will probably been kicked out of the nest by the parents or its try to fly itself and is on the ground somewhere.

Never interefere with a wild birds nest, All you can do is keep an eye on the parents see if they goto the chick wherever it is and keep feeding it.
Or you can look around the tree where the nest is and see if the baby is there if it is not fully feathered which it probably is not chances are if its fell from the nest it will have either hurt itself or died.

Mike