This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
I think there is only one brother because one single person can be brother for all sisters in the family.
Since there are 6 sisters and each sister has 1 brother, so in total there is only 1 brother...This 1 brother is the brother of all 6 sisters...... So the ans. is that there is only ONE (1) brother in the family...
1 5 1