Liam -> Blue Jay

I immediately thought someone in the corvidae family would fit Liam best. Ravens are famous for their puzzle solving skills, and many heroic deeds require that level of deep thinking. But at the same time he needs a bird that's got the same taste of style as Liam, though unfortunately I don't know of any birds with capes, so instead we'll have to settle on a corvid with beautiful, distinct coloring.

Duncan -> Pigeon/ Rock Dove

I thought Duncan should be a bird often overlooked by most people. Despite these pigeons ancestors being domesticated by humans centuries ago, they've now gone feral and are called pests, or Rats with Wings. Both Duncan and the Rock Dove would be lovely companions but are instead overlooked, unloved, and scorned... except by a few people.

(... oh I think a domesticated duck or chicken would work for Duncan. But I've got a soft spot for Pigeons ☺️)

Gustav -> Canadian Goose

You don't want to mess with either Gustav or a Canadian Goose. These geese are loud, loyal, and aggressive (when their boundaries are pushed). I'd say Gustav is slightly more gun-ho for a fight than the geese, but that's a pretty impressive feat within itself.

And last but not least, the blorbo himself!

Frederic -> Fancy Pigeon (breed; Old German Owl Pigeon)

So keeping pigeons isn't as common as it used to be, but by golly do people still do it! There are so many fancy breeds out there, some who have no chance surviving out in the wild. The only way these birds could exist is in captivity. Of course, some pigeons get loose every now and then, and join a wild flock of pigeons. This all made me think of Frederic; the fancy looks, the dependency, and running off on a new adventure!

(Plus this breed has the little neck ruffles that mimic Frederics collar. Tho I wonder if there's a bird that mimics the look of tassels... hmmm)

And I know you just asked about the princes, BUT.... I did the princesses too! Hehehe

Ella -> Peregrine Falcon

Ella's number one goal in life is to see and experience the world. While individual Peregrine won't see the whole world in their life time, the species is found all over the world; in every continent besides Antartica. Plus, Ella tends to act first, think later. She wont let anyone stop her. That could be translated to the Peregrine falcons need for speed. (A little bit of a stretch, I know, but I think Ella would enjoy being the fastest flying animal in the world, and who am I to deprive her of that?)

Rapunzel -> Mourning Dove

Have you heard these birds call? They have the sweetest, softest sound, it's my absolute favorite. Top tier. The Best. Hoo hoo ho, hoo hoo ho.... I gotta make my blorbo a mourning dove because they both share a similar vibe and I would die for both of them.

Snow -> Kea

Snow is silly but creative, smart but goofy, and that immediately made me think of the Kea. I think Snow would enjoy the kind of shenanigans the Kea gets up to, and even though Kea aren't known for it, I can see a Snow Kea using branches and twigs to make a masterpiece.

(Kea are more known for their destructive nature..... I guess Snow would just be a Kea channeling that energy into crafting instead akdkfgsakskkg)

(....honestly she could be a domestic duck too. Hmm. Now I'm not sure which I like more!)

Briar -> Major Mitchell's Cockatoo

If I know anything about parrots in captivity, it's that they are loud, demanding, destructive toddlers. No, Briar is nothing like a toddler, but just like tamed parrots, she's demanding, loud, and tactful. This Cockatoo has all of these traits, plus a beautiful rosey plumage and a crest that resembles Briars stack of hair. (If you squint!)

Aaaaaand that's it! That's all the princes and princesses done, there's no one left to turn into a bird :)

....

ExceptMaybeLilaAndRuffianBecauseWhyNot

Ruffian -> Turkey Vulture

So I dont have a compelling reason for this one, other than I imagined a sad Turkey Vulture with a blue cloak and couldn't get it out of my head. Ruffian is a turkey vulture because my brain told me so.

Lila - Chickadee

Ya know who's often underestimated despite how valued they are by the people around them? Lila and Chickadees! Think about it, Lila is valued by her mother and father only as an additional heir, not always taken seriously by Liam because she's his younger sister, but is capable of accomplishing lots and lots of things. Chickadees are often valued at birdfeeders for their plumage and iconic Chick-a-dee-dee-dee call, but by golly these birds have an impressive way of surviving the winter! They actually don't eat the seeds they collect, at least not yet. They hunt for insects during the spring and summer, and store the seeds in trees crevices and branches for the winter! And it takes a lot of brain power to memorize where all those seeds are located.

Cute, but underestimated. Lila and the Chickadee!

Aaaaaand that's it, I've reached the image limit. No more birds.

And I promise I didn't mean to make this response so long! It was just so fun to come up with what birds would describe who. Combing birds and heros guide... my new weakness

OH I DIDNT DO VAL AND I LOVE VAL. Okay, umm.... she also reminds me of a Canadian Goose tbh! But like a regular Canadian Goose, unlike Gustav, who is just a more aggressive Canadian Goose. Tho maybe she could be a domesticated goose??