Sure, young Harry belongs to the Houdinis, but, in the context of the sentence, the apostrophe is not needed, and is confusing. So, the Houdinis is bringing young Harry.....! Funny, that is! :)
Pastor Bob Ferguson and his wife, Joan, arrive at church. Bob always preached from his copies of the KJV translators' personal notes as well as the original Texus Receptus. Here you can see them carrying these into their church as they did every Sunday. Naturally he kept them in a treasure chest to protect them from grenade attacks.