That's a big no-no. Gambling with another person's money is a great way to lose that person's trust and friendship.
Only people who are addicted and cannot control them self are those who will borrow money from others as they would have lost theirs already and quite sure they will even lose out the others money and will not have anything to replay later. Thus this spoils the relations as well as not body loves this types of friends or relatives.
Yes. As I do not see anyone in his or her sane mind that would go through that length of using someone's fund to gamble when he sure must have known that would be some high level of risk. You cannot even gamble with money you cannot afford to lose in the first place, while putting the risk into play, and that is a high level of addiction as well as greed which I can actually attribute to laziness.
I feel lazy people are always the ones who are not ready to work to get money, but simply looking for fastest and easy means to get money even at the detriment of others.