Day 171: Capitalize mom and dad, and other relations, when used as names.

Capitalization rules may seem inconsistent, but they are not. For example, sometimes you capitalize mom and sometimes you don’t. However, you already know the rule that you capitalize people’s names and other proper nouns.

The same rule applies to mom and dad. When you use them as a name, you capitalize them, otherwise not. Consider this sentence.

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“Did Dad give Mom anything for her birthday?”

Here, “dad” and “mom” are being used as the proper name for those two people, so they get capitalized. Now consider this sentence.

“My mom and dad are at home watching a movie.”

Here, “dad” and “mom” are being used to describe a type of relative, not as proper names, so they don’t get capitalized.

This is the same reason why we don’t capitalize president when referring to the office of the presidency, but we do capitalize it when used as a name or part of a name, as in these examples:

“The president will address the troops at lunch.”
“The troops will have lunch with President Obama.”
“Mister President, do you have a comment on the food you ate?”