Will the trustee take all this money in every account even if we have not been in any debt together?

Your sibling who is filing bankruptcy will have to disclose their ownership interest in the accounts. Their share of the accounts would be considered an asset of their bankruptcy estate. Assets of a debtor are subject to a potential liquidation by a Chapter 7 Trustee. Liquidation typically does not take place unless there is unexempt equity. Generally, a Trustee would look at this situation and see 1/3 of each account as an asset of the bankruptcy estate. The other 2/3 of each account would belong to the non-filing siblings. This analysis could change depending on facts such as when the funds were deposited and where the funds came from. If you are concerned, you should talk to your sibling and see if their attorney will explain to what extent the accounts will be part of the bankruptcy estate. If there is a significant amount of money at stake, you may also what to consult with another attorney for possible representation.

I can't say whether or not the Trustee will take the money without more information. Since the nature of a joint account is that each owner is entitled to all the money in the account, he would certainly have a claim. On the other hand, if the total of all 3 balances is within the sibling's exemption amount, and the debtor properly exempts it, then the Trustee can't touch it. Perhaps your sibling's lawyer would be willing to discuss the issue with you. In any case, you can always discuss it with your brother or sister. Good luck.

Without other evidence, the trustee can take the share of the account owned by the bankrupt. So if there are 2 names as joint owners of an account, the trustee can take 1/2 that account. If there is evidence that one person put in all the money and that this person is the owner of the account, then the whole account belongs to that person and the trustee either gets nothing or the entire amount.

It will depend on who owns the money in the joint account. For example, if any one of the people on the account was able to legally remove all the money, the trustee could say that the brother filing bankruptcy had a right to 100% of the money in this account. If the ownership of the money in the joint account was to be split, the trustee would only take the share of the brother that filed bankruptcy.

I would see an attorney immediately, preferably prior to the filing.