- Up at the lighthouse, on Saoirse's 6th birthday, Ben looks out at the sea and at Bronaghs shell flute, his eyes tearing up. There's something about his expression that indicates how much he misses his mother, as though he's wordlessly wondering "Mum, what would you have done if you were still here?"
- Even sadder: the first time we see Conor after the Time Skip, hes doing the exact same thing, not even noticing Ben and Saoirse approach him at first. Its a clear sign how lost in grief for his beloved wife he is...
- During the scene where Saoirse finds her coat, she discovers a photograph of Bronagh. By the way she looks at it, she seems to not recognize her....meaning her father and brother never really told Saoirse about her mother.
- Granny's reaction to seeing Saoirse on the beach, apparently about to drown. That is some heavy adult fear.
- A lot of Granny's scenes are sad, despite her basically embodying the "Irish mammy" stereotypeConor's room is still perfectly intact, her concern over his depression in the face of his wife's apparent death...
- Ben's attitude towards Saoirse for half of the movie. He tells her a scary story about Macha the Owl Witch, and says if said witch came and stole their dad's feelings, no one would love her, making her think that her own brother doesn't love her. Poor terrified Saoirse hides under the covers, and Ben gets a My God, What Have I Done? moment.
- Conor snapping at Ben, leading the young boy to cry and the father being regretful over doing so.
- Just Conor in general. It's obvious just how happy he was in the prologue, with a happy marriage, a beloved son and a daughter on the way. When he loses Bronagh, he becomes a shell of his former self, trying to drink away the pain of losing his wife and believing he isn't able to be, and doesn't deserve to be, Ben and Saoirse's father.
- Ben and Saoirse's journey with their granny, they can only look miserable as she won't have them crying, Ben can only confide in Dan the Ferryman and won't even let Saoirse hold his hand.
- In the Holy Well, Saorise realizes the lights are leading her down into the water. With the most determined look a six year old can muster, she waits until Ben is distracted to jump in, leaving him to wrestle between Big Brother Instinct and his waterfright. What's even worse is when you realize why Saorise returns the shell horn to Ben back before going into the well: she does not expect to come back.
- Ben looking for Saoirse in the underground lagoon, unaware that Macha's owls have got her, he's almost lost hope by the time he encounters the Great Seanchai.
- Ben finally realizing what really happened on the night his mother "died" and Saoirse was born. He even cries tears of regret and shame.
- During the flashback in the cave, Ben finds Conor holding newborn Saoirse in his hands. Ben asks where Bronagh is, and Conor simply responds by showing him Saoirse, telling him that he must now look after her. Saoirse looks at Ben and reaches out to him, laughing... And Ben's face visibly hardens in anger. Ben was four at this time.
- What makes it hard for Ben to swallow is the cruel irony that washes over him: six years ago, he was so eager to meet his unborn sibling, wondering if he and the baby would become best friends. His mother saw such promise in her son, claiming he indeed would be the best big brother ever. Once he learns the truth about how Bronagh's apparent death was not Saoirse's fault, Ben is devastated to realize he had not upheld that promise, that for the past six years, he's been anything but a good brother to his innocent sister.
- Ben finding Saoirse encased in stone up to her midriff in Macha's attic, doubles as a Heartwarming Moment as he immediately apologises to her for being a bad brother.
- Macha's Heel Realization. After absorbing the emotions she's been capturing for centuries, all the Owl Witch can do is weep and look at her cameo of her beloved son, Mac Lir.
- Bronagh is probably a walking Tear Jerker. She falls in love with and marries Conor (a human). They have a son, Ben, and are about to have another baby. However, due to complications in the pregnancy, Bronagh transforms back into a selkie to save her and Conor's child. For the next 6 years, she was unable to be with her family. And when she does meet them again, it turns out to be a final goodbye. Saoirse stays with Ben and Conor of her own choosing. She shares one last kiss with Conor and gives some really helpful parting words to Ben. And then leaves forever....
- Mac Lir's sadness, as shown in a flashback. We don't know exactly what has made him so sad, but he's obviously extremely broken up about it, so much so that he cries an entire ocean, and it's made very clear how much anguish he's in. Not to mention how even when Macha takes away Mac Lir's sadness to ease his suffering, it turns him to stone.
- At the end, when The age of the ancient gods and heroes of Ireland is finally over, and their spirits rise up to finally venture to Tír Na nÓg...the last journey of Odysseus hasn't got anything on the sheer raw power of this scene, as Bronagh must leave her family behind again, in order to leave behind the land of menit's genuinely heartbreaking, especially for anyone with even a cursory knowledge of Irish myth.
Tear Jerker / Song of the Sea