What kind of bird is this? It's a little black above and a little white behind. Are they all black and white?

This kind of bird is called ten sisters bird, also known as white crying bird, fortune-telling bird and valley bird. It belongs to the golden-bellied finch family, with brown to dark brown feathers and a white abdomen to the waist. Every bird has different feather stripes. Mainly inhabiting South China, Himalayas, Myanmar, Malaysia and other Southeast Asian regions. Ten sister birds are lively and easy to domesticate. Ten sisters have strong nesting ability and are the best at brooding among all birds.