Haunted Mansion closure for overlay

Planning first DL trip in 2016. Was planning to go Sept 18-24 for five park days. It would kill me if Haunted Mansion is closed for the Christmas overlay. When does it usually close and reopen? Do they close “It’s a Small World” for a holiday overlay? This may be a once in a lifetime trip and I don’t want to miss either attraction.

http://touringplans.com/disneyland/attractions/its-a-small-world/closures

http://touringplans.com/disneyland/attractions/haunted-mansion/closures