Jen,
And I agree Dayna comes across as younger than 21 or so, but an extremely sheltered life will do that. {Jen contemplates many of her early-20s female students in Japan as cases in point}. I was always a bit disappointed they didn't play up that "unworldly" aspect of Dayna more in the show--she should have had a hell of a time with group dynamics and social mores. I know, I
know,
they all did, so she didn't stand out much. :)
Ever since I first saw Dayna in 'Aftermath', I felt (although I was only 11) that she behaved like someone younger than about 20, due to what was obviously an 'extremely sheltered life'. In terms of why this unworldly aspect wasn't played up, I feel that because she was the youngest member of the crew, the rest treated her like a younger sister, who had led a sheltered life, but who was useful, knowing all she did about weapons, as well as being a good fighter. Even Soolin, the experienced gunfighter, had words of respect for her abilities.
Murray