Lines of brother and sisters:
You can observe very easily your lines of brothers and sisters because Palm line not only tells the story about life but also explores much information about your family and relationships with them. On your palm you can observe lines of brothers and sisters too which clearly can tell you exact numbers.
If these lines are weak and broken, then the health of your brothers and sisters will also be weak. Generally if this line is wide and deep, than it indicates numbers of brothers and the narrow lines indicate the number of sisters. Line which breaks on the way or which is cut into pieces indicates that the brother or sister will die in the life time of that person. If these lines are not present on your palm than this is clear indication of not having any brother or sister.
Infect this line is also a very helpful line in palmistry which tells lot about any person's family life and the relationship with them.