How old are they if the difference between 3 brother's ages is also prime?

Question

Dean, Sam and Castiel are three brothers.
Interestingly their current age is prime.
What's more interesting that difference between their ages is also prime.

Answer 1

All primes are odd except 2 so thier differences will always be even except for 2 and 3 case. So for the differences between 3 prime numbers to be prime one of the 3 numbers should have to be 2.

So 2,5,&7 is a possible answer because
5-2=3
7-5=2
7-2=5
Are all primes.