Relationship in a Firebase database type

relationship_database.json

{
  "Events": {
    "event_one": {
      "event_name": "Global event",
      "event_location": "Lagos Ikeja",
      "event_created": 16082017,
      "event_active": "active",
      "Speakers": {
        "0": "speaker_one",
        "1": "speaker_two",
        "2": "speaker_three"
      }
    },
    "event_two": {
      "event_name": "Developerlearn  friday session",
      "event_location": "Iwaya Sabo . Yaba",
      "event_created": 16082017,
      "event_active": "active",
      "Speakers": {
        "0": "speaker_one",
        "1": "speaker_two"
      }
    }
  },
  "Speakers": {
    "speaker_one": {
      "speaker_name": "Olatunde Owokoniran",
      "speaker_email": "[email protected]",
      "event_created": 16082017
    },
    "speaker_two": {
      "speaker_name": "Femi Taiwo",
      "speaker_email": "[email protected]",
      "event_created": 20082017
    },
    "speaker_three": {
      "speaker_name": "Mclord Adeola",
      "speaker_email": "[email protected]",
      "event_created": 22082017
    }
  }
}