Definition of Sandwich Generation

Do you ever heard about "Sandwich Generation"? It must sound novel. 

Sandwich generation is designation given to people who must fulfill the needs of a large family. Like a sandwich, it has many layers. Themselves, parents, and children. They have to take care of their elderly parents. At the same time, there are children who must be raised to adulthood. 

Sandwich generation is often found in developing countries, where a person's relationship with their family is so thick.