The life spam of a Elf and a Half elf its way bigger than the Human..
Like Shadowheart she looks that way but if im not mistaken she is 40 already..
(she says this when yu find the Book in Sharran stuff in act 3.. she coments when yu get the book about her.)
its becouse of this that they start to look old when they reach hundreds yeas and stuff like that..
for elf i beleave its more.. for then to look old.
(just to put in perspective.. if your tav is a Human and yu do end up with Shadow.. yu will die before her.. haha)
i beleave its the same for the other Romanced races in the game like Laezel, astarion..
(i actually beleave its pretty fair for Jaheira still be alive becouse the way she looks.. and if yu noticed she is really damaged when in camp clothes. her hands specially)
looks like she went tru some Hard stuff between games and managed to keep alive.. badass.
Something that i dont know if yu guys find about her its in her house.. maybe it was cut content.. but she has a Ritual to actually become younger/imortal.. bring minsc when yu visit her hide sanctuary and yu will find easy the secret door to get the sword and this scroll im talking about.. the game dosent gave yu a option to convince her to do the thing.. but she even talks about it..what that thing is supposed to do with her. i just forgot the name..
another thing.. Shadow Father is Full elf.. and look at him.. the dude dosent look like young get it ?
or is he Half elf too ?