The death of plants is usually not a good thing, especially when it is due to someone neglecting to water them, which implies that the friend is not thoughtful and one should not be happy about it
Consider the staetement "I asked my friend to water my plants while I was on vacation but she didn't and they died.". Based on this statement, is "I was really happy when I got back from vacation and found out that my plants died because my thoughtful friend didn't water them" a true statement? Yes/no/unknown