It's Ian Somerhalder!
Although at 27, Robert Pattison is older than many of his Twiilght co-stars, Ian Somerhalder wins this round of Who's Older! Ian is 34, more than seven years Rob's senior.
For the record, if we're talking their undead alter-egos, Damon Salvatore vs. Edward Cullen, Ian still wins. Damon was born in 1839 and changed in 1864, while Edward was born in 1901 and changed in 1918.
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