In the episode where Rachel was dating a guy named Russ that looked exactly like Ross.

I once heard that Russ was David Schwimmer's real brother, and not David playing both roles. Is this true?????

Thanks.

David played both characters. He credited Russ to a friends name though but it was him that played the dual characters.

Really? I didn't know that. When I saw the name when they played the credits I thought it was that guy.