Let be ,my means x ; and sister means y;

7 years ago

y= 2x+2=32

  2x=30

    x= 15;

That means 7 years ago i was 15 and my sister was 32;

2 years ago

Hear we have 5 years gap ; that means i am 20 and my sister is 37 in 2 years ago.

At prest means hear we get 2 years gap
That means now i am 22 and my sister is 39.

The answer is 22 of that boy at present age.