Puzzle #199: Siblings

Susan has twice as many brothers as sisters. Her brother, Tom, has twice as many sisters as brothers. How many male siblings are there, and how many female siblings are there in Susan’s and Tom’s family?

Submit your answer to Gene Wirchenko <genew@telus.net>. Your answer should be in the form of a proof. That means to show how your answer must be correct. The deadline is Wednesday, March 29, 2017 at noon Pacific Time. I will post the answer shortly after.