Matilda went in at 16 months and to be honest it seemed a bit early, it took around 2 months to adjust for her but she has always had sleep issues so we knew it would take longer. She went into the cot because she was climbing in & out of the cot and it was getting dangerous. You have time though if it doesn't work now, you can try again in a month & it may be easier for Mya to understand things then.