If your husband's name is also on the account then yes they can take it, but they can't unless you have a hearing and they tell you. Your bank shouldnt allow them access without a court order. If the account is only in your name, then they can't touch it. You are not the biological parent and the child support is not your responsibility. I suggest if you want to protect your money, then put it in a separate account in only your name. Good Luck.
Yes they most certainly can go after your assets. The government does not fool around with those who owe child support. Thus it is always wise to keep all of your finances and assets separate when marrying a divorced spouse with children. Plus I would highly suggest you put your Real Estate into a trust if you have not already done so.
If it is a joint account that you share with your husband, yes they can, IF they have a judgment to do so.
If you are not the biological mother or father of the child then you have nothing to do with child support. Child support cannot be taken from the spouse of the person who owes child support.