Can a non party appeal?

Kutlesa v. Kutlesa, 2013 ONCA 549:

[5]          There is a threshold problem today, however: Mr. Kotsiou was not, and is not, a party to the Family Law Actproceeding between the Kutlesas from which this purported appeal springs.  He has taken no steps in Superior Court to be added as a party or to set aside or vary the order of Parayeski J., although a motion to stay that order was brought before another judge and dismissed on the basis that it should be brought before Parayeski J.  A renewed stay before Parayeski J. has not been pursued to date.