In most states, the process of disclaiming an inheritance allows you to avoid receiving it, but does not allow you to direct it. You should check with local counsel for the implications of disclaiming the bequest. It may end up with your descendants, anyway.
If you direct it to someone else in your family you will be making a gift; however, if you simply refuse the gift and the controlling Will or the rules of intestacy (whichever apply) cause the amount disclaimed to pass to such individuals then no gift is implied although you may have issues with certain creditors. You'd be best served by consulting a local attorney who can review your precise facts and give you complete advice.
Very truly yours,
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