The heartbreaking meowing of cats may be caused by the estrus period. Generally, this happens to female cats when they are in estrus, especially at night. It is normal for female cats to howl to attract male cats, so Don't worry. When the cat reaches the estrus period, you can take the cat for breeding. If you do not want the cat to have children, you can consider sterilizing the cat to relieve the discomfort of the cat during estrus.