Grayson? Well, surname names having been on an upward trajectory for a while. It also shares the popular “ay” sound with mega-hit Aiden and its variants. It’s also an alternative to “Jackson”, which has consistently charted very high for the past few years.

Atticus? A lot of popular boys’ names start with “A” — see Aiden again, and Andrew, Alex, Anthony, Austin, Aaron etc — and the “s” ending recalls other perennial favorites like Marcus and Nicholas. Literary names are having a serious moment also. Atticus is the right combination of accessible and intellectual.

Brie? It’s a punchy little name a la top-10ers Chloe, Ava, and Mia. It also resonates with longtime favorite Brianna. “Br” names are in — see Brantley, another listed name, as well as Brayden (ick), Brandon, and, yep, Brianna. “Briella” contains the popular Ella; it’s also long been a diminutive of equally popular Gabriella. “Aubrey”, another listed name, also contains the “brie” sound. It’s probably rising for similar reasons. It’s also a soundalike to popular Audrey AND has the auspiciously upbeat “-ee/ie/y” ending so popular with the current wave of names. This one’s a no-brainer.

Luna? I’m sure Harry Potter has something to do with it, but this name definitely also got a boos from the current popularity of “L” names. It’s a stylish alternative to Lily, Lila, Lydia, Lia, and the rest.

Basically what I’m saying is: any cultural trend tends to be more complicated than you’d guess at first glance. That’s definitely true of names. I get that simple explanations make for more concise slide-shows, but these explanations also suffer for being reductive, and sometimes — like in the case of the “connection” between Angelique and Dark Shadows — they’re just patently unlikely. Names are complicated. That’s part of the reason why they’re awesome. Amirite?

Case in point: Atticus. This name gets a lot of attention because of TKAM, however I have seen Atticus linked to quite a few claims that “Roman names” are a hot item. Now what explains the Roman name trend? It was certainly well underway before The Hunger Games movie. So what is causing these “Roman” sounding names to be appealing and sound more approachable as actual modern given names? I would argue that the cultural atmosphere that is (for whatever reason) more accepting of “Roman” names could be what is giving the Finch fans the courage to actually use his name — if TKAM is, in fact, the reference in mind. There’s just a lot affecting the culture and naming attitudes.

And I know for sure that Grayson was on the rise way before Revenge came out. Like sleepyjaime said, Drop Dead Diva came first. Though I do think I heard quite a bit of it even before that came out. I know I’ve loved Graydon since I was little because of Trevor Graydon from Thoroughly Modern Millie, not sure exactly when Grayson came into my conscientious.

However, apparently there is a town/municipality called Brielle in the Netherlands so I think that’s the best choice to use if they want to call Brielle a place name, or better yet list them as Americanized diminutives of Gabrielle/Gabrielle like you said.

I would assume that Brie/Brielle share an older root word though.