Name those Siblings #1

Name those sibling! Based on what they look like, what do you think these kids are called? And how old do you think they are?

1. Oldest sister:
http://www.istockphoto.com/file_closeup.php?id=13415444

2. Teenage sister:
http://www.istockphoto.com/stock-photo-11493312-smiling-teen-in-t-shirt.php

3. Brother:
http://www.istockphoto.com/stock-photo-11742106-smiling-cute-little-boy-showing-thumbs-up-over-white.php

4. Twin brothers:
http://www.istockphoto.com/stock-photo-11779419-happy-young-twin-boys-with-glasses-smiling-outside.php

5. Sister:
http://www.istockphoto.com/stock-photo-3581180-portrait-of-little-girl-standing-in-field.php

6. Youngest sister:
http://www.istockphoto.com/stock-photo-12627403-pretty-little-girl-in-white.php