defendants, claiming their full share of the annual rental income
from the property.
 One of the defendants, Megapro Property Management
Ltd., has been the manager of the property since late 2009,
following the illness and death of the prior property manager,
Gabriel Zimmerman. It has collected the rents, but is holding
back part of the entitlement of the respondents because of
a claim to part of their share of the funds by the estate of
Mr. Zimmerman. That claim is based on two separate acknowledgments purporting to be signed by each of the respondents in
2002. The acknowledgments gave Mr. Zimmerman a 25 per cent
interest in the respondents’ respective entitlements to the rental
and sale proceeds of the property.
 In 2011, the respondents sued Megapro and the other
defendants for the funds Megapro has been holding back. In
2016, the defendants brought the motion under appeal for an
order adding the estate as a necessary party to the action. The
defendants also sought an interpleader order allowing Megapro
to pay the funds it is holding into court to await the outcome
of the issue of the validity and effect of the acknowledgments.
The estate participated in the motion, supporting the defendants’ argument that it should be added as a necessary party to
 The motion judge dismissed the defendants’ motion on the
basis that the estate’s claim is statute-barred, as Mrs. Zimmerman, the estate trustee, discovered the acknowledgments in 2010
following her husband’s death. On this appeal, the appellant is
the estate. The defendants did not participate on the appeal.
B. Factual Background to the Motion
(1) Acquisition and management of the property on Danforth
 In September 1982, the defendant, 3030 Danforth Ltd.,
purchased the property at 3026-3032 Danforth Avenue in Toronto.
3030 Danforth was incorporated for the purchase in order to
reflect the ownership interests of the share owners as follows:
Faigie Abrahamovitz, two common shares; Frances Spiro, one
common share; T.M.W. Consolidated Holdings Inc., two common
shares; and Michael Berens, one common share.
 The relationships between the various parties are as
follows. The defendant Lois Kalchman was Michael Berens’
niece. Upon his death, she inherited his common share in the
property. The defendant Mark Berens was Michael Berens’
nephew. Mark Berens is a director and officer of the defendants