I'm not entirely sure which specific 'Seligman telling the Nikki story' you are referring to. There could be many Seligman's and Nikki's, and without more context, it's hard to give a detailed account.
Well, if Seligman is Martin Seligman (a well - known psychologist), perhaps the 'Nikki story' could be related to his research on positive psychology. Maybe it was a case study or an anecdote he used to illustrate certain concepts like learned helplessness or resilience. But again, this is just speculation without more details.