"Of course" isn't always going to be obvious to everyone. Perhaps you don't realize it, but these sorts of comments come across as very rude sometimes. Please try to be mindful of that.
I don't mean offense, but with some things, it is obvious and it makes me wonder how the ones who don't realize it didn't see it.
Here, we have Momma who was already repeatedly shown in a swan-like gown. And these last few pages, well, Dad is just being very heavy-handed with the "fly away" comment and other imagery.
It's like going through Final Fantasy X and then actually being shocked when it turns out that Yuna is supposed to die at the end of her journey. Like... have you been stuffing your fingers into your ears and closing your eyes the entire game? They drop heavy hints of it from the very beginning.
Let everyone read and digest this stuff at their own pace, please.
Also like zebra said, not everyone knows about the Swan Maiden Tale. Out of the four years I have been reading this comic, a good portion of it I just assumed Beauty's mom was either a figment of imagination for Beauty (in some of her dreams) or an enchantress.
Everyone does everything at their own pace, including realizing things. Sometimes some things are more obvious than others to some, and very obscure to others. You cannot judge others through your own experiences and lens, as you can clearly see that not everyone has heard that story (I am one of them), so you should not expect everyone to know everything you do.
From what I can find after a quick search, this doesn't fit the traditional swan maiden story, but rather seems to be loosely based on animal spouse tales in general. For example, in the usual swan maiden tales, the man steals the woman's feathers/skin so she cannot transform back into a swan and forces her to marry him. From what we've seen thus far, it appears that, at least to begin with, he has no idea she is a swan maiden and didn't steal her skin. So, either he found out somehow or asked her and she left (similar to the Crane Wife), or someone else has stolen her skin. I'm basing this on the Wikipedia for Swan Maidens if anyone's interested in checking it out themselves.
This actually makes me wonder how she birthed their daughters. Did she lay eggs with each one containing a daughter like Leto did for Zeus's children: Pollux and Helen, or did she give birth to them like a human woman would.
I feel reasonably confident that eggs would have caused comment. I can't recall any mention of swan maidens laying eggs in folklore, either. (Though I also can't recall any mention of live birth, so I suppose canon is silent.)
Now THAT takes love. You do not marry to be happy. You marry while being aware that there will be unhappy moments, unpleasanteries and imperfections, but you love each other anyway.
Oh man, I found out my husband liked pro wrestling about five years into our marriage. I have never looked at him the same since. Sadly, he will not agree to take me to a match.
Ooooooh. That's so interesting that he guessed that she was a swan maiden, but never felt the need to press the issue and confirm that. I thought that he wasn't in the know, but that makes their relationship that much stronger and more intimate.
There is so many mythical characters in the world. In scandinavia there is one beautiful looking woman, but hollow when you get the chance to see her back. She wants to marry a young man. When they get married she devours him to fill that hollowness. When he refuses, she will devour him right away. So, as soon as her eyes fall on a man she likes, he is doomed. Always had strong women, the scandinavians.