He did not try to look further into it but says that his mother and siblings have been acting with so much resent towards him. Anton, my friend is now trying to get in touch with someone about it because he was not pleased with the person that informed him. He believes that his mother offered that informer money to try and get information about the trust fund in Anton's name. Question is --- could there be a condition saying that Anton will only be informed upon the death of his mother? Why has he not been contacted and its been 4 years since the passing away of his mother.
Please see my answer to your other question under "Financial Planning." That may give you insight as to how trusts work.
Anton's best bet would be to set up a brief appointment with an estate planning (trust) attorney in the state in which he lives. An initial consultation probably won't cost much - likely just a few hundred dollars or so - and I would think the information would be well worth the dollars he spends on finding out the answer.
However - a very short answer to this question is YES - a trust can be set up which only distributes assets to a beneficiary in the event that another person passes away. There are a number of reasons a trust might be set up like this (see my previous answer).
IF such a trust exists - and is currently managing assets on behalf of Anton in secret - it is likely that it can be discovered and an attorney familiar with these matters will be able to find the trust. After all, it has to pay taxes, so it leaves a trail that can be followed. However, discovering any more details may be very difficult - especially if the trustee (the person in charge of the trust assets) has been instructed by the trust document itself to keep all information about the trust private. The attorney will know the applicable laws in both Anton's state - as well as the state which governs the trust itself. They may not be the same; other state's trusts are often used for both privacy as well as additional asset protection. For example, Nevada, Alaska, and Delaware are known to have laws which are heavily weighted toward asset protection as well as privacy.