Should you capitalize words like “Honey,” “Sweetheart,” and “Darling?”
The current usage does not capitalize these words. Remember to be consistent.
From the CMOS Forum:
Q. Are terms of endearment capped when used as a form of address, for example, in “Bring me my shoes, Precious” or “Turn off the TV, Darling”? I believe this used to be a rule, but with the trend toward “down” styling, most editors perhaps have thrown it out.
A. Chicago’s preferred style has always been to lowercase pet names, but you can’t go wrong unless you’re inconsistent, since the issue is guided by preference rather than rule.
Q. Hi, Chicago! My team has a question about kinship names. We understand words like Mom, Dad, and Grandma get capped when standing in place of a name, but we often see son and sis lowercased, even in direct address (e.g., “Well, son, let me explain” and “What’s the matter, sis?”). Is it because those are more terms of endearment than actual stand-ins for the name? Or should Son and Sis be capitalized too?
A. You’re right that Mom, Dad, and Grandma are used by children who wouldn’t address their elders by first name, whereas terms like son and sis are more often meant as generics rather than to replace a name, and that makes lowercasing them appropriate. In gray areas writers may use their discretion.