Question 1149674
This problem is faulty.  If you set up equations according to the description, you will find a false equation as a result.


A, Ama
b, brother
{{{system(A=b+5,b+4=(A+4)-6)}}}


{{{b+4=(A-2)}}}
{{{b+4=(b+5)-2}}}
{{{b+4=b+3}}}
{{{4=3}}}------------FALSE


The description given can never happen.
Age difference between brother and sister will never change.