This drabble is set in the mid-1950s. At that point in Colombia, Isabela's relationship was illegal - consensual same-sex relations were decriminalized in 1981, with same-sex marriage being legalized by the Constitutional Court in 2016. Given the two men dancing a rather coupley-looking dance in "Waiting on a Miracle," I've headcanoned that most of the people in the Encanto are at least tolerant, if not completely accepting... a much better situation than in the US at the time!
Incidentally, the Catholic Church was only finally written out of the Colombian constitution in 1991. Until the 1970s, it had the final word on any marriage involving a Catholic.
Mirabel and Bruno's marriage? Weird but legal then, even weirder but still legal now, provided everyone's over 18. A very high profile example was Julio Cesar Turbay, who married his then-15-year-old niece Nydia in 1948 in a secret wedding at a Catholic church. Turbay went on to be elected President of Colombia in 1978, with Nydia as First Lady. They divorced shortly after his term in office and got it annulled by the Catholic Church on consanguinity grounds a few years after that, but had four kids together. Had they done things the "right" way by getting a dispensation for the consanguinity before they married, they likely would not have been able to get that annulment.
Getting that dispensation is one of the things Mirabel and Bruno are dealing with in my "Under the Sacred Canopy".
In Spanish, Camilo is that kid's "primo" (first cousin) via Bruno, but instead of "first cousin once removed" via Mirabel, he's the kid's "tío segundo" (second uncle), and the kid is his "sobrino segundo" (second nephew).