What does it mean that swallows fly into the house at night?

According to the ancient custom in China, swallows represent auspicious and peaceful birds, so it is auspicious for swallows to fly home. Swallow: In ancient times, it was regarded as a bird with long life and good luck. And Yan is homophonic with Yan and Yan, meaning peace, and the swallow returns to report peace. If you build a nest at home, it will bring good luck and good luck. Hope to adopt! !