my cousin wants to go along with me but he's 18, but just wants to watch. can he walk around all the casinos with me without incident from security?

No, he has to be 21 to set foot on the casino floor. Otherwise, the casino could get fined like crazy.

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"I am in so far in blood, that sin will pluck on sin" - Richard III

hi David,if you just want to watch then every casino's have their own rule but if you really want to play i'll suggest to go online casino sites, they are in number.I usually play on http://www.casino21.dk this is totally free site.

Don't be stupid Fistar every 18 y/o kid knows he can play online, that's not what he was asking. Anyway, If you are under 21 you can't stand in one spot. You must keep moving.He must also stay on the main pathways and not go within the casino area. It's not much of an experience, but it should keep the kid from getting kicked out.