If you want to teach your younger brothers/sisters(in the age group 10-16) programming then you should consider Microsoft Small Basic which is a wonderful language for kids in that age group .
Microsoft Small Basic is a simplified variant of the BASIC programming language introduced by Microsoft in October 2008. With a bare minimum of concepts, Microsoft touts this as an easy programming language for beginners to grasp. The language itself has only 14 keywords, and the environment is beginner friendly with a straight-forward interface.
Microsoft Small Basic works on Windows XP, Windows Vista, or Windows 7 and you need to have Microsoft .Net Framework 3.5 .