We took our daughter for the first time when she was 6 months and we had a great time. You can take your son on all rides that don't have a height requirement: pirates, Haunted Mansion, small world, most of the rides in fantasyland, Buzz, Winnie the Pooh, astro orbitor. There are too many to mention them all. There are also lots in California Adventure: Little Mermaid, Monster's Inc, Bugsland, etc
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