Has a guy ever told you he’s going kill himself after breaking up with him?

So today I heard something that really shook me. My mom told me that the guy my sister broke up with, told my sister he can’t live without her and wants to kill himself. Also he recently he lost his job and said it was because of the breakup, he said he wasn’t functioning because she left him so they fired him.

Has anyone ever experienced this?

I never take these things lightly, do you think a stable person would be acting this way?

Need advice please. I live overseas so I’m not there with them.

How would you handle this situation, and what should my sister do?

My sister 19 years old and in college. He is the same age as well.