Gordon v. Goertz [1996] 2 SCR 27 (Relocation case) at para. 50:

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?

Moge v Moge [1992] 3 SCR 813 (Spousal support)

The second observation I wish to make is that, in determining spousal support it is important not to lose sight of the fact that the support provisions of the Act are intended to deal with the economic consequences, for both parties, of the marriage or its breakdown.  Marriage may unquestionably be a source of benefit to both parties that is not easily quantified in economic terms.  Many believe that marriage and the family provide for the emotional, economic, and social well‑being of its members.  It may be the location of safety and comfort, and may be the place where its members have their most intimate human contact.  Marriage and the family act as an emotional and economic support system as well as a forum for intimacy.  In this regard, it serves vital personal interests, and may be linked to building a “comprehensive sense of personhood”.  Marriage and the family are a superb environment for raising and nurturing the young of our society by providing the initial environment for the development of social skills.  These institutions also provide a means to pass on the values that we deem to be central to our sense of community.

Conversely, marriage and the family often require the sacrifice of personal priorities by both parties in the interests of shared goals.  All of these elements are of undeniable importance in shaping the overall character of a marriage.  Spousal support in the context of divorce, however, is not about the emotional and social benefits of marriage.  Rather, the purpose of spousal support is to relieve economic hardship that results from “marriage or its breakdown”.  Whatever the respective advantages to the parties of a marriage in other areas, the focus of the inquiry when assessing spousal support after the marriage has ended must be the effect of the marriage in either impairing or improving each party’s economic prospects.

Michel v Graydon, 2020 SCC 24 (retroactive child support) at para. 31

As to Mr. Graydon’s conduct as the payor parent in this case, it is really this simple. When a payor parent fails to pay the appropriate amount of child support, the recipient parent is left to shoulder the burden. If the recipient parent does not have the means to provide their child reasonable support, the child suffers. Both the recipient parent and the child may experience hardship because of a payor parent’s neglect. Seen in this light, it bears repeating that retroactive child support is not exceptional relief (D.B.S., at para. 5): there is nothing exceptional about judicial relief from the miserable consequences that can flow from payor parents’ indifference to their child support obligations. This is not to say that hardship is required to ground an award for retroactive child support, as there is also nothing exceptional about relief that creates a systemic incentive for payor parents to meet their obligations in the first place. Just as an order of child support is intended to provide children with the same standard of living they enjoyed when their parents were together (D.B.S., at para. 38), an order of retroactive child support provides an (albeit imperfect) remedy where that does not occur. And as this Court recognized in D.B.S., “courts are not to be discouraged from defending the rights of children when they have the opportunity to do so” (para. 60).