There is no widely documented film, show or viral origin for this clip, and it appears to be a short user-generated soundboard recording rather than a line taken from a known character. That anonymity is part of its appeal on meme and editing communities, where a generic motherly sneeze can fit almost any cute, awkward or surprising moment without carrying outside context. Creators reuse it because it is instantly readable, easy to drop into short videos and endlessly reusable as a small comic beat.