Where Do You Nest Your Sass Breakpoints?

I love nesting my @media query breakpoints. It’s perhaps the most important feature of Sass to me. Maybe I pick a method and do it like this:

.element {
  display: grid;
  grid-template-columns: 100px 1fr;
  @include breakpoint(baby-bear) {
    display: block;
  }
}

That’s straightforward enough. But what if my element has several sub-elements and the breakpoint affects them as well? There are different approaches, and I’m never quite sure which one I should be doing.

I could duplicate the breakpoint for each child:

.parent {

    @include breakpoint(desktop) {
    }

    .child {
        @include breakpoint(desktop) {
        }
    }

   .child-2 {
        @include breakpoint(desktop) {
        }
    }

}

The compiled CSS comes out to something like this:

@media screen and (min-width: 700px) {
  .parent {
  }
}
@media screen and (min-width: 700px) {
  .parent .child {
  }
}
@media screen and (min-width: 700px) {
  .parent .child-2 {
  }
}

Or, I could duplicate the children under the first nested breakpoint:

.parent {

    @include breakpoint(desktop) {

       .child {
       }

       .child-2 {
       } 

    }

    .child {
    }

   .child-2 {
    }

}

That results in:

@media screen and (min-width: 700px) {
  .parent .child {
  }
  .parent .child-2 {
  }
}
.parent .child {
}
.parent .child-2 {
}

Or I could do a combination of the two. Neither of them feels particularly great because of the duplication, but I’m not sure there is a perfect answer here. I err a little more on duplicating the media query, as it seems less error-prone than duplicating selectors.