How To Make A Kitten Throw Up?

my cat just threw up she was fine this morning and hasnt eaten in 2 days put her down for a while to eat things but i cant find anything thats the only thing that could cause this?

How can I get my cat to stop throwing up after eating? My sister’s kitten is throwing up every time he eats. He throws it back up, too! What do I do? She doesn’t want us to take him away… what should we do?!