What is the test for joint custody of a child when one parent says that they cannot communicate effectively with the other parent?

[16] The Ontario Court of Appeal in Kaplanis v. Kaplanis (2005), 194 O.A.C. 106, 249 D.L.R. (4th) 620, 10 R.F.L. (6th) 373, 2005 CanLII 1625, [2005] O.J. No. 275, 2005 Cars­well­Ont 266, set out that one parent professing an inability to communicate with the other parent does not, in and of itself, mean that a joint custody order cannot be considered. However, there must be some evidence before the court that, despite their differences, the parents are able to communicate effectively with one another. When the child is so young that he or she can hardly communicate her developmental needs, communication is even more important.