I have a 9 year old, and two BCI's. She LOVES them. They are very docile, curious creatures. To reassure your wife, just get a nice secure enclosure. And males tend to stay smaller. He's just a baby in this picture, but show her how sweet he is! (Those are my daughters toes)
And he really is the most mellow little laid back dude. Boas are awesome, good luck!
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