You should be happy that you have a bright child. The presence of a retarded child in the same creche will not affect your daughter’s growth or development. Mental retardation is not contagious! Children do imitate others whom they see. It is possible that she saw one child doing something different and tried out the same thing. It is good for your child to come upon children with different talents and abilities. She will learn that everyone is not alike. You could tell her not to put her fingers in her mouth or put her tongue out. Tell her that it is not necessary to do exactly what someone else does. She could be told that the child who does such things is still a baby in many ways and should be helped to grow up and be like the others. We are in favour of Inclusion, not Exclusion.