Is the gray swallow born?

Gray swallows are eggs, not viviparous.This bird is also called gray silk or African silk, which is a kind of silk bird. The most famous of its similar type is the golden bird, also known as Baiyan.The gray swallows have no fixed reproduction period. Usually after maturity, they can be paired. At the same time, some materials are required to make it as nest. After making, it will lay eggs. Usually a nest can produce 2-6 pieces, hatching, hatching, incubationIt takes more than two weeks.