How has consent or court approval been considered in the context of medical malpractice cases?

The consent or court approval has been considered not a matter of capacity but rather one of formality: Kerr v. Kerr et al., 1933 CanLII 17 (SCC), [1934] 2 D.L.R. 369, [1934] S.C.R. 72.

The Parliament of Canada has exclusive legislative authority in regard to the capacity of persons to marry, and it is silent on the minimum age. At common law, derived from ecclesiastical law, the marriage of a child of less than seven years is void. The marriage of a male older than seven years but younger than 14 years, or a female older than seven but younger than 12 years, is voidable at the instance of the infant upon his or her attaining the requisite minimum age. Further, a marriage where either or both parties were under age becomes validated if they continue to cohabit as husband and wife after reaching the age of capacity: Kerr v. Kerr, supra.