I'm not a teacher, but I've found this:
I hope it helpsWhich of the following are correct?
1. Happy holidays from the Smith’s
2. Happy holidays from the Williams’
3. Happy holidays from the Smiths
4. Happy holidays from the Williamses
5. Happy holidays from the Smiths’
6. Happy holidays from the Williamses’
ANSWER: Only numbers three and four are correct. Here's why:
The first two examples are wrong for two reasons. First, the apostrophe makes the names possessive, and when we send greetings, the greetings are from us, not from something we own. The names “Smith” and “Williams” would need to be in the possessive case only if the greeting were from Jane Smith’s hamster or John Williams’s goldfish.
Second, they are wrong because they are singular. The greeting is supposed to be from the entire family, not from an individual. Yet when we place the apostrophe where it is in examples one and two, we have made a singular word possessive instead of making it plural.
The middle two are correct because in both cases the words are plural but are not made possessive. To form the plural of any name that does not end in “s” or another sibilant (more on sibilants below), we simply add an “s.” Thus the name "Smith" becomes plural when we add an "s" to make "Smiths."
"Williams" is a little tougher because it ends with an "s." Names (and all other words, for that matter) that end with the sounds “s,” “sh,” “ch,” “z,” or “x” (what we call sibilants) are made plural by the addition of “es.” Thus the name “Williams” in its plural form is "Williamses." Here are some other correct examples.
These names end in sibilants and are thus made plural by adding "es":
Happy holidays from the Bushes (plural form of the name Bush)
Happy holidays from the Birches (plural form of the name Birch)
Happy holidays from the Joneses (plural form of the name Jones)
Happy holidays from the Foxes (plural form of the name Fox)
These names do not end in sibilants and are thus made plural simply by adding "s":
Happy holidays from the Swansons (plural form of the name Swanson)
Happy holidays from the Bradleys (plural form of the name Bradley)
Happy holidays from the Berrys (plural form of the name Berry). *Notice that we do not drop the "y" and add "ies" to proper names.
In another tip, we will discuss situations in which the apostrophe should be used with names in order to show possession. But for now, remember that when greetings are from the entire family, the name needs to be plural, not possessive. Of course, another option is to avoid both the plural and the possessive by writing “Happy holidays from the Birch family.”
Holiday Greetings: Naming Names