This happened Monday night and then again this morning. But my poor Frosty has like made this wierd meow noise like it sounds like he's crying mom mom mom mom, then like 5-10 seconds later, he throws up quite a bit. What could be the cause? I had him on Science Diet Hairball Control food, then that ran out and bought a 10 lb bag of regular science diet food for kittens since the pet store clerk told me that kittens do not have hairballs. I am beginning to not believe her. When he was on the hairball control, never once threw up until we came back on the regular food. Help me here please.