Question 438852
Not enough info to know when you will never be exactly 3 times older than your son. you didn't give us your exact birth dates and times.
We can approximate though assuming you both already had birthdays this year 
2011-1957=54
2011-1996=15
(x+54)=3*(x+15)
x+54=3x+45
9=2x
4.5=x
add 4.5 to 2011

check
58.5=3*19.5
ok