"little sister" meaning in English

{
  "forms": [
    {
      "form": "little sisters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "little sister (plural little sisters)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Female family members",
          "orig": "en:Female family members",
          "parents": [
            "Family members",
            "Female people",
            "Family",
            "Female",
            "People",
            "Gender",
            "Human",
            "Biology",
            "Psychology",
            "Sociology",
            "All topics",
            "Sciences",
            "Social sciences",
            "Fundamental",
            "Society"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Siblings",
          "orig": "en:Siblings",
          "parents": [
            "Family members",
            "Family",
            "People",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Synonym of younger sister"
      ],
      "id": "en-little_sister-en-noun-Ajnf74OC",
      "links": [
        [
          "younger sister",
          "younger sister#English"
        ]
      ],
      "raw_glosses": [
        "(informal) Synonym of younger sister"
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "younger sister"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "little sister"
}

{
  "forms": [
    {
      "form": "little sisters",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "little sister (plural little sisters)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "en:Female family members",
        "en:Siblings"
      ],
      "glosses": [
        "Synonym of younger sister"
      ],
      "links": [
        [
          "younger sister",
          "younger sister#English"
        ]
      ],
      "raw_glosses": [
        "(informal) Synonym of younger sister"
      ],
      "synonyms": [
        {
          "tags": [
            "synonym",
            "synonym-of"
          ],
          "word": "younger sister"
        }
      ],
      "tags": [
        "informal"
      ]
    }
  ],
  "word": "little sister"
}