Sum of Twin Primes is Divisible by 12

Suppose  
\[p, \; p+2\]
, both greater than 3, are twin primes. Then their sum is divisible 12.
\[p+(p+2)=2p+2=2(p+1)\]

\[p\]
  is odd so  
\[p+1\]
  is even hence  
\[2(p+1)\]
  is divisible by 4.
Working modulus 3, and noticing that since  
\[p \gt 3\]
  we must have  
\[p \equiv 1, \; 2 )mod \; 3)\]
.
\[p \equiv 1 \; (mod \; p) \rightarrow p+2 \equiv 0 \; (mod \; 3)\]
  so  
\[p+2\]
  is composite contradicting that  
\[p+2\]
  is prime.
\[p \equiv 2 \; (mod \; p) \rightarrow p+2 \equiv 1 \; (mod \; 3)\]
  so  
\[p+p+2 \equiv 2+1 \; (mod \; 3)\]
.
Hence  
\[2p_2\]
  is divisible by 4 and 3 so is divisible by 12.

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