Answer:
5
Explanation:
Using b and g to refer to the boys and girls in the family, we have that
For Steve: 3(b-1)=g (since his brothers are b-1, since he does not count himself)
For Sasha: g-1=b (the same reasoning as before)
We can the calculate that
g=b+1
3(b-1)=b+1
3b-3=b+1 => 2b=4 => b=2
g=2+1=3
There 3 girls and 2 boys in the family, meaning 5 children in total.