MEMORANDUM AND ORDER
DAVID J. WAXSE, Magistrate Judge.
This matter is presently before the Court on Plaintiff Yarbary's Motion for Leave for Joinder of Parties (ECF No. 70) and Motions for Leave to File 4th Amended Complaint (ECF Nos. 80 and 88). In this ERISA breach of fiduciary duty case, Plaintiff Yarbary requests leave to join one additional plaintiff under Fed.R.Civ.P. 19 and twenty-seven additional individual defendants under Fed.R.Civ.P. 20(a). He also requests leave to file his proposed fourth amended complaint, which adds claims and allegations against the defendants to be joined. For the reasons set forth below, the Court will permit Plaintiff Yarbary to join the additional defendants, but not the additional pro se plaintiff. Plaintiff Yarbary will also be granted leave to file his proposed 4th Amended Civil Complaint, but with the caption and "Parties" section modified to include the names of the defendants he has been granted leave to join in this action.
I. Factual Background
Plaintiffs Yarbary and Mabone, both proceeding pro se, filed separate actions claiming that they are entitled to the proceeds of their deceased mother's employee benefit plan. Plaintiffs are surviving children of Katherine D. Towles, who was a participant in a group life insurance policy issued by Defendant Unum Group Corporation ("Unum") to Ms. Towles' employer, Defendant Martin, Pringle, Oliver, Wallace, & Bauer, LLP ("Martin Pringle"). Plaintiffs allege that their mother originally designated them as beneficiaries under her life insurance policy but that her employer, Martin Pringle, and her husband, defendant William S. "Red" Towles, conspired together to forge a beneficiary designation to name Mr. Towles as the beneficiary.
Plaintiff Yarbary filed his complaint on December 10, 2012. Plaintiff Mabone filed his complaint on December 28, 2012. Upon Defendant Unum's motions, the cases were consolidated on March 12, 2013, designating Plaintiff Yarbary's case, Case No. 12-2773, as the lead case.
On June 18, 2013, Plaintiff Yarbary filed a motion for joinder of parties. A week later, on June 25, 2013, he filed a motion for leave to file his fourth amended complaint. After Defendants Martin Pringle and Unum filed responses pointing out that Plaintiff Yarbary failed to attached his proposed amended complaint to his motion, Plaintiff Yarbary then filed another motion (ECF No. 88) on July 10, 2013 with his proposed amended complaint attached. His proposed 4th Amended Civil Complaint adds allegations against the twenty-seven individual defendants he seeks to join in his motion for joinder of parties.
II. Motion for Joinder of Parties
A. Request for Joinder of Another Pro Se Plaintiff
Plaintiff Yarbary requests leave to add one additional plaintiff to this case pursuant to Federal Rule of Civil Procedure 19. Specifically, Plaintiff Yarbary requests leave join his older sibling, Bryan G. Mabone, as another pro se plaintiff in this action. As a non-attorney, Mr. Yarbary may represent himself in this action, but he may not act as an attorney for any other individuals. This prohibition includes moving that his sibling be joined as another pro se plaintiff. The right to proceed pro se in civil actions is guaranteed by 28 U.S.C. § 1654. It is well-established, however, that this right to proceed does not encompass the right to proceed pro se on behalf of the interests of another. Because pro se means to "appear for one's self, " a person may not appear on another person's behalf in the other's cause but must be litigating an interest personal to himself. An unlicensed layperson thus may represent only himself and not another individual before a district court. As Plaintiff Yarbary is proceeding pro se and may represent only himself in this action, his request for leave to add his sibling as another pro se plaintiff in this action is therefore denied.
B. Request for Joinder of Additional Defendants
Plaintiff Yarbary also requests leave pursuant to Federal Rule of Civil Procedure 20(a) to join as defendants five partners of Defendant Martin Pringle and twenty-two officers and directors of Defendant Unum. In support of his request, he asserts that the five additional Martin Pringle partner defendants he seeks to join in this action "jointly held or hold the authority to control or manage the administration of the plan." He further asserts that the twenty-two Unum defendants he seeks to join in this action "jointly held or hold authority to control and manage the operation and administration of the plan." Plaintiff Yarbary contends that joinder is appropriate because he asserts a right to relief against the defendants to be added to this matter which arises from the same series of transactions or occurrences as the existing defendants. He also contends that questions of law apply and are common to all defendants and that the facts are common to all defendants to be added.
Federal Rule of Civil Procedure 20(a)(2) allows permissive joinder of a defendant if:
(A) any right to relief is asserted against them jointly, severally, or in the alternative with respect to or arising out of the same transaction, occurrence, or series of transactions or occurrences; and (B) any question of law or fact common to all defendants will arise in the action.
Rule 20(a)(2) thus sets out a two-part test for permissive joinder of a defendant. First, the Court must determine whether any right to relief is asserted against the existing defendants and the defendants to be joined that arises out of the same transaction, occurrence, or series of transactions or occurrences. If this part is met, then the Court must determine whether any question of law or fact common to all defendants will arise in the action. The purpose of Rule 20(a) is "to promote trial convenience and expedite the final determination of disputes, thereby ...