I'm not sure if Maki was really close with her brother. Probably just the average relationship siblings have with each other? I didn't wanna turn the story of her brother depressing or anything but the saddest part about it is around the time he got sent to jail his wife gave birth to their third child.
^ his daughter
(I think she is the first child)
some english articles if anyone wants to read more into it
http://www.japan-zone.com/news/2008/...oto_yuki.shtml
http://www.japan-zone.com/news/2007/12/12/index.shtml