Kinship is the quality or state of being kin, and refers to the relationships with one’s relatives. Normally you would not have to or want to prove your relationship with someone unless you intend to gain from such a relationship or it is getting in your way of making something happening, and this is where kinship verification comes in.
Kinship verification refers to the process of verifying your relationship with a relative. It usually happens when you intend to travel abroad. For instance, your spouse is working and living in China and you plan to visit him or her. You might be required,when applying for a visa, by the Chinese embassy or consulate to show documents that can prove your relationship. A notarized kinship certificate may also be demanded when a teenage boy or girl is applying to study overseas. To put it in a nutshell, averified kinship certificate is normally destined to use in a foreign country that you are travelling to, and is asked for to either justify your reasons for travel or prove the source of your finances during the trip. Either case, you first must submit the original documents to be authenticated by the concerned party in your own country and then send them to the embassy or consulate of the country for which they are intended to be legalized.
There are other situations where kinship verification might be demanded, such as when inheriting the assets and wealth of a deceased distant relative whom you might not have even heard of. However this might be very rare.