Sferruzzi v. Allan, 2013 ONCA 496:
 Gordon v. Goertz,  2 S.C.R. 27 is the seminal case on mobility in family law cases. In it, the Supreme Court set out the principles that govern such matters. Paragraphs 49-50 of Gordon contain the following summary of those principles:
1. The parent applying for a change in the custody or access order must meet the threshold requirement of demonstrating a material change in the circumstances affecting the child.
2. If the threshold is met, the judge on the application must embark on a fresh inquiry into what is in the best interests of the child, having regard to all the relevant circumstances relating to the child's needs and the ability of the respective parents to satisfy them.
3. This inquiry is based on the findings of the judge who made the previous order and evidence of the new circumstances.
4. The inquiry does not begin with a legal presumption in favour of the custodial parent, although the custodial parent's views are entitled to great respect.
5. Each case turns on its own unique circumstances. The only issue is the best interest of the child in the particular circumstances of the case.
6. The focus is on the best interests of the child, not the interests and right of the parents.
7. More particularly the judge should consider, inter alia:
a) The existing custody arrangement and relationship between the child and the custodial parent;
b) The existing access arrangement and the relationship between the child and the access parent;
c) The desirability of maximizing contact between the child and both parents;
d) The views of the child;
e) The custodial parent's reason for moving, only in the exceptional case where it is relevant to that parent's ability to meet the needs of the child;
f) Disruption to the child of a change in custody;
g) Disruption to the child consequent on removal from family, schools, and the community he or she has come to know.
In the end, the importance of the child remaining with the parent to whose custody it has become accustomed in the new location must be weighed against the continuance of full contact with the child's access parent, its extended family and its community. The ultimate question in every case is this: what is in the best interests of the child in all the circumstances, old as well as new?
Appellate Intervention is Warranted
 The Supreme Court of Canada has confirmed the narrow scope of appellate review in all family law matters relating to custody and access: see Van de Perre v. Edwards, 2001 SCC 60,  2 S.C.R. 1014, at para. 11. An appellate court is entitled to intervene only where the trial court committed a material error, seriously misapprehended the evidence, or made an error in law: Van de Perre, at paras. 11-12.
 In my view, appellate intervention in the present case is warranted for two reasons: the motion judge erred in law in placing the burden of proof on Mr. Sferruzzi, and he seriously misapprehended some aspects of Mr. Sferruzzi's evidence and failed to afford it proper respect.
The Burden of Proof
 The motion judge erred in law by placing the burden of proof on the appellant. This error is evident from the following passage at p. 23 of the motion judge's reasons:
I am called upon [to] decide whether, based on all of the factors, there is sufficient evidence to convince me that the proposed move and the related changes to Mason's access to the respondent are in his best interest. [Mr. Sferruzzi] has made the motion and bears the onus of satisfying me in that regard. [Emphasis added.]
 The second point in the extract from Gordon, set out above, makes it clear that once the threshold requirement of demonstrating a material change in the child's circumstances is met, the judge "must embark on a fresh inquiry" into the best interests of the child. Accordingly, it was an error for the motion judge to approach the motion on the basis that the appellant had to persuade him that the relocation was in Mason's best interests. As the threshold had been met, the ultimate question on the motion was: what is in Mason's best interests in all the circumstances, old as well as new? (See Gordon, at para. 50.)