Tenn. Code Ann. § 32-3-112

If the residue of the decedent's testamentary estate or the residue of a revocable trust created by the decedent that becomes irrevocable at the settlor's death is devised to two (2) or more persons, the share of a residuary devisee that fails for any reason passes to the other residuary devisee, or to the other residuary devisees, in proportion to the interest of each in the remaining part of the residue, unless the decedent's will or trust agreement or § 32-3-105 provides for a different disposition.