First off, a co-debtor stay is imposed immediately when a Chapter 13 is filed. That means any collection action, including phone calls, are supposed to cease immediately for the co-borrower even though he or she did not file their own bankruptcy.
Second, a Chapter 13 bankruptcy plan payments appear to toll the statute of limitations whether or not the trustee makes the payments once a creditor files its proof of claim that survives any debtor objections.
Florida’s tolling statute does not require payments to be voluntary:
95.051 When limitations tolled.-
(1) The running of the time under any statute of limitations except ss. 95.281, 95.35, and 95.36 is tolled by:
…
(f) The payment of any part of the principal or interest of any obligation or liability founded on a written instrument.
Contrast with (1) (e):
(e) Voluntary payments by the alleged father of the child in paternity actions during the time of the payments.
(Emphasis added)
This means that a Chapter 13 can act to stop collections on non-discharged debt, but eventually that debt will become due unless dealt with during the bankruptcy in some fashion.