... It did not indicate when the child died or their specific age.

So we just know they were somewhere between 0 and 5.

Even assuming the child was old enough for the first dose ("under five" could mean a newborn), they may have had a valid medical exemption. There isn't enough detail (in the article, or in the report it references) to say for certain. I admit that the probability is low.

A child under five years old has died of measles

This is the first sentence of the article.

So, my comment is accurate.

In Ontario, MMR is at 12 months and varicella (chickenpox) is separate at 15 months.

Other provinces, territories and states in Canada/US have variations and some include MMRV instead of MMR followed by Varicella.

MMRV is scheduled routinely at age 4-6.

An overview of the routine childhood schedule can be seen here.

The full ontario schedule can be found here, with the routine childhood schedule being on page 3.

By the way for anyone wondering why bother vaccinate against chickenpox, it's because chickenpox and shingles are the same thing. If you never get chickenpox you never get shingles. Shingles fucking sucks and causes blindness, untreatable pain and other miseries.