Tenn. R. Civ. P. 17.03
Whenever an infant or incompetent person has a representative, such as a general guardian, conservator, or other like fiduciary, the representative may sue or defend on behalf of the infant or incompetent person. If an infant or incompetent person does not have a duly appointed representative, or if justice requires, he or she may sue by next friend. The court shall at any time after the filing of the complaint appoint a guardian ad litem to defend an action for an infant or incompetent person who does not have a duly appointed representative, or whenever justice requires. The court may in its discretion allow the guardian ad litem a reasonable fee for services, to be taxed as costs.
Tenn. R. Civ. P. 17.03
Advisory Commission Comments.
17.01: Rule 17.01 generally requires that actions be brought in the name of the real party in interest. Certain persons may sue in their own names without having to join the party for whose benefit the suit was brought; the list of such persons expressly includes executors, administrators, guardians, bailees, trustees or an express trust, persons to whose rights others have been subrogated, and any other persons authorized by statute to sue in their own names. The Rule is similar to Federal Rule 17(a), but unlike the federal rule, Rule 17.01 authorizes suit by a party in the party's own name even though another has been subrogated to the right which the party seeks to enforce.
17.02: This Rule deals with capacity, and not with standing to sue, which is the subject of Rule 17.01.
17.03: Rule 17.03 establishes a uniform practice regarding suits brought on behalf of an infant or incompetent person, and, when justice requires, allows suit by next friend and requires that the court appoint a guardian ad litem.
Advisory Commission Comments [2000].
The addition of subsection (2) to Rule 17.02 merely recognizes the holding of Tennessee decisions applying Tennessee statutory law. See, e.g., Fain v. O'Connell, 909 S.W.2d 790, 794 (Tenn. 1995). The enforceability of judgments continues to be governed by the substantive law. See Federal Deposit Insurance Corp. v. Tyree, 698 S.W.2d 353 (Tenn. Ct. App. 1985).