a younger sibling
a cousin who is descended from an ancestor who is/was a younger sibling to oneself's or one's spouse's (such as a child of a younger sibling of one of one's parents or a grandchild of a younger sibling of one of one's grandparents)
a person younger than oneself but of the same generation
a child or a student

pronoun used to refer to any person (oneself, the addressee, or any third person) described by the noun em above
pronoun used to refer to any person (oneself, the addressee, or any third person) described by the noun em above
pronoun used to refer to any person (oneself, the addressee, or any third person) described by the noun em above
pronoun used to refer to any person (oneself, the addressee, or any third person) described by the noun em above
pronoun used to refer to the girl or woman in a romantic relationship

small; smaller