Eomer and Eowyn only talk to each other once in the films
but they communicate so much.
When Eomer first returns with a wounded Theodred, an entire dialogue is shared between Eomer and Eowyn without a single word passing between them.
This mutual look of concern, they're both on the same page.
Eowyn then goes on to look at Theodred's wound. It's interesting that Eomer now looks curious above all things, he's waiting on Eowyn's judgement.
Eowyn looks at the wound and grimaces. It's bad. Theodred isn't going to survive this.
She looks to Eomer, who looks back at her in grim resignation.
They go to Theoden to inform him of the situation. As Eomer walks by Eowyn, he doesn't speak to her or interrupt her, but he puts his hand on her back as he passes. Even when the focus is on other things, he is giving her that gesture of support and fondness. That it is done without fanfare shows that this sort of affection is commonplace.
They both stand before the throne, both of them united in their attempt to reach through to their uncle. They're a team, a unit.
Eomer throws down proof that Saruman, who Grima is trying to portray as a friend to Rohan, is sending his soldiers to terrorise their people.
Eowyn gives Grima a death glare, challenging him to refute her brother's accusations. She's on Eomer's side, Eomer's team.
Eomer sees Grima looking at Eowyn, and knows what he wants. It fills him with fury.
Eowyn sees her brother choking Grima against the wall. She looks on in cold silence, then walks away.
When Aragorn reveals that the beacons have been lit, Eowyn rushes into the throne room, drawing to a stop at Eomer's shoulder. They wait together for Theoden's judgement.
When it comes, and Theoden sends Eomer to muster the troops, Eomer bows, but even before he has fully straightened up, his eyes go to his sister.
Again, no words exchanged, simply a look of common understanding. They both know what the risks are, they both know what is at stake, for the world, for their country, for their family.
Before Eomer leaves, he touches Eowyn's arm, before walking away.
With Eomer gone, we see a steely determination come into Eowyn's eyes. Now there's something Eomer's missing, now Eomer's back is turn and there's something about his sister that she's keeping from him. She's riding to battle.
The one time they speak to each other, they're in opposition. About Merry, about Eowyn, about war.
The words are harsh. Eomer is stern, Eowyn is defensive.
But Eomer puts his hand on Eowyn's shoulder. He doesn't say "I don't want you to get hurt, I don't want you in battle", but that hand on her shoulder, tells the audience that's exactly what he's saying.
Those small moments of physical affection culminate in one great moment, when stern, stoic Eomer discovers Eowyn on the battle field, and breaks down in tears, cradling her and rocking her like she's a child.
And his devotion to her is ultimately shown in him sitting small and hunched, tucked in on himself, crouching down in armour for what seems to have been a lengthy space of time, as he sits by her side, waiting for her to be healed.
This is such an effective way of showing to an audience that two characters love each other, when there is a limited time window. The movie needed to crack on to cover the ground it needed to cover, and with so many important dynamics to reveal to the audience, the creators needed to be time effective. Eomer and Eowyn don't share much screen time, but the looks exchanged, the passing moments of intimacy, tells us clearly that these are two people greatly fond of each other, and have been fond of each other a long time.
The lack of spoken dialogue almost enhances it. Little is said between them because little needs to be said. They already know. The one time they do speak, it's when they're quarrelling, because that's the only moment when they need to use words. The rest of the time, a gesture, a look, is enough.
