Keep in touch with your family and friends before and after bull run, the happiness of profit can also drive one crazy which can make one do something unreasonable such as getting drunk, driving recklessly and many more. To those who will see this thread, please keep this words in mind.
Anyway, it would be better to just teach them what can happen during a bull run, and a bear run as well so that they will not commit heinous crimes, or do anything bad because their investment is down by a huge percentage. I've heard some news regarding investors who are unfortunately committing suicide because of their wrong decisions. A quick google search can give you many articles regarding them.
Like what others said already, thanks for sharing your advice. This might help 1 or 2 users here, and change them in a positive way.