Answer:
Vicarious consumption refers to showing a family's (or individual) social status through the things that they purchase, i.e. keeping up with the Joneses.
Advertising links the desire to be socially recognized and accepted with the possession of material goods. This is exactly what vicarious consumption is all about. E.g. if most of your classmates use expensive Nike shoes, you will feel different if you wear cheap shoes. If you add this feeling of being different plus Nike ads reinforcing that feeling, then you will at least consider buying Nike shoes, or whichever brand is popular among your friends.
The same thing applies to your parents, e.g. if your parents' friends all buy large SUVs, then your parents will feel different if they buy a sedan even if they would be happy with it. Again, advertisement plays an important role here because it shows SUVs as the appropriate cars for successful families (and the larger the SUV, the more successful you are).