Trudy has normal limb development and delayed mental development compared to other children. Upon admission, she was 1 year old and she was careful in her new surroundings. At the age of 2 years, she could walk alone, was curious about new things, her hand-eye coordination was improved, and she could express her emotion. At the age of 4 years, she could have eat and drink independently and could recognize people, places and objects, but her expression was poor. At the age of 6 years, she was receiving the special education in the institute. Her self-management was improved under the guidance of the teacher, but her accepting ability was not good compared to other kids of her age. At the age of 8 years, she could speak simple numbers and words, could draw, could finish some simple jigsaw puzzles, and could play with the toy blocks. Now she can wave her body along with the rhythm of the music, can read simple children’s songs and words, and can count 1-10, but her expression is still poor. Trudy is open, likes music, can get along well with other kids, likes helping people, and wants to be praised. She is happy when watching cartoons and walking outside.