I think she was the best sister she could be being the slayer and all..

I don't think I'd have the patience to put up with Dawn as a sister at the best of times, never mind while dealing with being a slayer, a parents death and coming back from the dead. I'm amazed Buffy didn't just snap and throttle her :)

I think she could have done a better job. Dawn has been systematically abandoned by everyone. She only misbehved because she wanted some attention.Buffy isolated herself from every one, I was excited at the start of season 7 when they were slaying together

she sacrifice for her

No she wasn't a good sister at all, look as season 6 where she ignores her for most of the season. Buffy didn't die for her, she died to save the world "That was her gift." What I don't get is the fact that A. Buffy was not her sister, but more like her mother (DAWN WAS MADE FROM BUFFY'S DNA, That make her mom not sister.) B. Why didn't anyone (I.E. Willow the science geek) Point that out.

tinkymel She did sacrifice herself for Dawn. It was suppossed to be Dawn who jumped, Buffy jumped and died so Dawn wouldn't have to.

And in season 6 Buffy was traumatised after being ripped out of heaven. The fact that she was in too much emotional pain to babysit Dawn doesn't make her a bad sister, in fact I think the fact that Dawn was so unsupportive and wasn't understanding at all to Buffy after the trauma she went through makes Dawn the bad sister. Buffy was in a very dark place and rather than help her or be glad she was alive again all Dawn could do was whine that she didn't get enough attention.

Buffy calls Dawn her sister because the monks made her feel like her sister and gave them a lifetime of memories of being sisters. Thats why nobody got technical about it, also if you're going to get technical, since Dawn was the key for years before being related to Buffy she was neither her sister nor her child.

Outside of sacrificing herself for Dawn, I didn't get the impression she was a good sister or guardian to Dawn. Dawn kind of drops out of the story after her Key storyline is through, and that gives me the impression that's actually how much attention Buffy pays to her.