The lawyer told the assembled family that their wealthy uncle had left his entire fortune to his cat.

Should the word lawyer or uncle be capitalized in this sentence?

No. Neither of those words should be capitalized.

In this sentence, the word "lawyer" should be capitalized, but the word "uncle" should not.

To understand why, let's break down the rules of capitalization:

1. Proper nouns: Capitalize the names of specific people, places, organizations, and so on. For example, "Mary," "London," "Microsoft." In this sentence, "lawyer" is not a specific person's name, so it doesn't qualify as a proper noun and should not be capitalized.

2. Titles: Capitalize titles when they are used as part of someone's name or as a direct address. In this case, "the Lawyer" is being used to refer to a specific individual, so it should be capitalized.

3. Common nouns: Capitalize common nouns when they are part of a specific name or title, such as "Father John" or "Queen Elizabeth." In this sentence, "uncle" is a common noun that does not refer to a specific name or title, so it should not be capitalized.

Therefore, in the given sentence, "lawyer" should be capitalized as "Lawyer," while "uncle" should remain lowercase.