I think the brother's death was a lot more sad *because* of the fact that he goes through all of that, and has a much harder time than the sister. he is very stoic about his suffering and never really seems to complain. I'm not saying that the sister's crying *wasn't* sad or relatable, but she just seemed to cry in a very causal and general manner, and she wasn't really presenting it in a way that showed that her real *pain* and misery was there like it was for the brother. the brother putting his sister's weight upon his shoulders, as opposed to the daughter who's having herself looked after and having sacrifices being made for her, is why the brother's death is a lot more sad. but again, I wouldn't say it was sad enough to make me cry because of the lack of any music (I mean, there's a time and a place for a lack of music to create emotion but this wasn't it) and the fact that they really didn't put enough emotional emphasis on the mother dying - for all we know, this was the only person the two characters *really* had some kind of emotional connection to, and they kind of just put up with it without any tears - and then the movie seems to be implying, with the grumpy auntie in the next part after her death being something that the two characters put up with rather well, that the mother's death wasn't life-changing for them emotionally. I know I keep putting stress on the mother, but honestly, the loss of a parent at *that* age really ought to have made more of a dent, and the movie focuses way more on the survival aspects of their life in the economically ruined/war-hit japan. a bigger emphasis or even a role for the mother really would have made the difference, because she dies with the context of a) the audience having really no idea who she was, and b) her death ultimately being emotionless - that's not something the audience, looking through the eyes of a child, can relate to in my opinion
with something like cowboy bebop, the main character (spoiler alert) dies for the woman he loves, whom herself dies in his arms, and his death scene is a very martyr-esque death, because he dies to kill somebody who deserved it (from memory, it was the person who kills his girlfriend, or at least causes her to die). and then when he finally dies, the music is *incredibly* emotional. it truly sounds like death and sadness. also, the main character's character is so immortal~ throughout the whole series that the fact that he dies essentially to kill this person really shows his determination to fight for that woman he loved, meaning that a totally stone-cold and cocky fighter is reduced down *so* much by love. if you honestly find this less emotional, given this context, I'd be concerned:
https://www.youtube.com/watch?v=uJqUEc1fUEwthe fact that, in GOTF, the two characters don't really die for anything (well, maybe the brother) except for simply avoding starvation, really retracts from the emotions, because it's not *driven* by emotion, but rather purely trying not to die, and to keep on living. we can all relate to emotions like love, but can we really relate to starvation without any feelings of long term loss? also, in terms of character change driven by emotions that we're meant to cry from, I don't really know how starvation and getting scratched up really counts for very much overall. also, the two characters are reunited in the end (through death and spirit), which really makes it seem not like a sad ending but more like a happy one. in CB, it is an ultimately lonely death for the person involved.