Alexa-Marie died in hospital after police were called to the family home in Queen Bee Court, Hatfield, at 9.30pm on Wednesday.
In a statement released through police, Alexa-Marie's family paid tribute to the youngster:
We are completed stunned and devastated that our beautiful little girl has been taken from us so suddenly.
She was truly the most gentle, loving, happy and amazing little soul we had the pleasure of knowing. We would be asked to be left alone to grieve at this traumatic time.
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