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I have a situation. My 3yr old son has been going to preschool and he loves it until recently, he's clinging on to me and crying begging me not to leave and it's really breaking me down. The last time he acted like this was at a daycare where they weren't being attentive to him. I've asked his teachers if anythings changed for him and they say no.. 
This is being up bad memories with the other daycare. Nothing has changed in our home life and I ask him why he is so sad at school and when I ask his teachers they have no clue. What should I do I don't want to remove him from the program I just want to get to the bottom of it..