When dd2.5 was about 1 or so she crawled into ds's sleeping tent he had at the time and found that he had strung up a fake spider web and spider. This was a real shock - for the next couple of weeks everything was 'scawy spider' this and 'scawy spider' that. She was freaked! Scared. It was just too much for her little self, but eventually she got over it.
Sounds similar...how old is your ds?

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