It could be a child is born with a particularly sensitive temperament and then experiences anxiety - producing events because of slight parenting errors. (tribecaplaytherapy.com)
Dogs with sensitive temperaments can be ruined by these methods. (johnknowsdogs.com)
Other kids with more sensitive temperaments are not able to do any of this unless they've had a day or at least an evening to readjust. (attachmentparenting.org)