Questionnaire with a variety of child item types (as used in the QuestionnaireResponse page links section)

{
  "resourceType" : "Questionnaire",
  "id" : "child-rel-demo",
  "meta" : {
    "versionId" : "1",
    "lastUpdated" : "2023-03-03T03:05:07.9531803+00:00"
  },
  "extension" : [{
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
    "valueCode" : "fhir"
  }],
  "url" : "http://example.org/Questionnaire/child-rel-demo",
  "title" : "Demo form on R5 spec QR page",
  "status" : "draft",
  "publisher" : "HL7 International / FHIR Infrastructure",
  "contact" : [{
    "telecom" : [{
      "system" : "url",
      "value" : "http://www.hl7.org/Special/committees/fiwg"
    }]
  }],
  "item" : [{
    "linkId" : "grp1",
    "text" : "grp1",
    "type" : "group",
    "required" : true,
    "repeats" : true,
    "item" : [{
      "linkId" : "grp2",
      "text" : "grp2",
      "type" : "group",
      "item" : [{
        "linkId" : "Q1",
        "text" : "Q1",
        "type" : "string",
        "repeats" : true
      },
      {
        "linkId" : "Q2",
        "text" : "Q2",
        "type" : "string"
      }]
    },
    {
      "linkId" : "Q3",
      "text" : "Q3",
      "type" : "string",
      "required" : true,
      "repeats" : true,
      "item" : [{
        "linkId" : "Q4",
        "text" : "Q4",
        "type" : "string"
      },
      {
        "linkId" : "grp3",
        "text" : "grp3",
        "type" : "string",
        "item" : [{
          "linkId" : "Q5",
          "text" : "Q5",
          "type" : "string"
        }]
      }]
    }]
  }]
}