Is it a kind joke or a malicious insult to say "you are sick" casually between friends and relatives?

People may think that you are scolding her (him). You think she (he) did something wrong, so you just casually said. Also, that person is very sensitive to this sentence, and it is unreasonable to hear her good friend say this sentence, which caused her anger. But it should be okay. Not accepting an apology is just a moment of anger, and you should forgive it in a few days!