Does it really need to tell them? That might possible if they will ask then but for as long as they don't bother to ask me, I'd rather keep quiet and keep it secret.
Not was hard for me, I may call myself selfish for not telling others but I think it was not an issue, sometimes we have to be silent especially when it talks about money. For security reasons, we have sometimes not bulgar to anyone around us, not unless if they belong to your family.