My cat who hasn’t throw up since I got him, recently threw up 3 times. He is 1 years old, turning 2 soon. He threw up again about a week after the 1st time and about 3 days the third time. What could be wrong with him. He never eats grass because I know that makes them throw up. I have him on hills prescription food because he had diarrhea when he was younger, but he’s been eating that for awhile now with no problems.