If you want to sponsor your wife, husband, child, mom or dad you have to make a certain amount of money. Or you have to have a certain amount of financial assets to be able to bring your love one to the US or get them a green card.
The following is the amount of assets you must make
if you are supporting 2 people you must have $19,662 in annual assets
If you are supporting 3 people you must have $25,737 in annual assets.
If you are supporting 4 people you must have $29,812 in assets.
If you primary sponsor does not have enough asset you can get a co-sponsor to make up the difference.