Plural Form of “Brother-in-Law” (Helpful Examples)

Plural forms are usually simple to work out. Most of the time, you add an “s” to the end of a noun to show that there are multiple entities. When that noun is hyphenated with multiple words, like “brother-in-law,” there comes a problem. This article will help you understand it.

What Is the Plural Form of “Brother-in-Law?

The plural form of “brother-in-law” is “brothers-in-law.” The simple trick to remember this is that you can have multiple “brothers,” but there is still only one “law.” Therefore, “brother-in-laws” can never be grammatically correct as the plural form.

brother in law plural

The same rules apply regardless of the relationship you have with the “-in-law.” You would say “sisters-in-law” for the plural of “sister-in-law” and “fathers-in-law” for the plural of “father-in-law.”

Only the relationship is modified into the plural form:

  • My brothers-in-law are coming to town later this evening. Do you want to meet them?
  • I thought she mentioned that her brothers-in-law were coming here tonight!
  • My sisters-in-law need a bit of help. I’m going to see what I can do for them.

What Is the Plural Possessive Form of “Brother-in-Law”

The plural possessive form of “brother-in-law” is “brothers-in-law’s.” You have to use the plural form, which is “brothers-in-law” with an “‘s” ending. This “‘s” ending is commonplace in most possessive forms to show that one noun owns another.

It’s not particularly common for the plural possessive form of “brother-in-law” to come up. Nevertheless, it could happen, and you might benefit from checking out these examples to see how it works:

  1. My brothers-in-law’s restaurant is being sold on the market today. I hope it goes well.
  2. These are both of my brothers-in-law’s homes. You’ll have to ask them whether you’re allowed to stay here.
  3. His brothers-in-law’s antics always seem to get him into trouble. I’m not sure why he always lets that happen.
  4. My sisters-in-law’s awards far outweigh anything that I’ve managed to do in my youth.
  5. I think her sisters-in-law’s manners could do with a bit of work. I’ve never really got on with them all that much.

The plural possessive form only works when multiple “brothers-in-law” (or “sisters-in-law”) own the same object or a similar group of objects. If you’re referring to more than one “in-law” relation, you can use this form.

What Is the Singular Possessive Form of “Brother-in-Law”

The singular possessive form takes the singular form “brother-in-law” and adds the possessive “‘s” to the end of it. This is a much simpler form that only refers to one “brother-in-law” owning an object. The rules are the same regardless of relation.

You should use “brother-in-law’s” when you’re referring to the singular possessive form. This shows that your “brother-in-law” owns an object. “Sister-in-law’s” is correct if you’re talking about what your “sister-in-law” owns.

This time, the “s” does come at the end of “law,” but only because it comes after an apostrophe. This is standard practice whenever the possessive form comes into play.

  1. I would like to see my brother-in-law’s idea, please. I think he has a good one.
  2. His brother-in-law’s dog is getting us all into trouble. Isn’t there anything we can do about that?
  3. I thought this was your brother-in-law’s place. Where is he? Why hasn’t he come over to talk to us?
  4. I’m going to my sister-in-law’s. I think I’ll be spending most of the evening there, so you’ll have to make yourself dinner.
  5. This is his sister-in-law’s umbrella. I should probably return it to her before she realizes it’s missing.

Sometimes, the object can be omitted from the sentence. Saying “I’m going to my brother-in-law’s” is an acceptable sentence. It usually suggests that you’re going to his “house,” but “house” is left out of the sentence.

Brother in Law or Brother-in-Law?

Hyphens must always be used when linking a compound noun relating to a relationship. Therefore, “brother-in-law” is correct, but “brother in law” is not. The same applies to other relationships, such as “sister-in-law” and “mother-in-law.”

You must keep the hyphens present whenever you include these types of relationships. This is standard practice in English and follows relevant AP Style and other style guidelines.

Final Thoughts

The plural form of “brother-in-law” (or any familial relationship) adds an “s” after the family connection. “Brothers-in-law” is the only correct way to write the plural form. If you want to use the possessive form, you should include an “‘s” after either the singular or plural form.