My 2.2 year old DD has started refusing to respond to us unless we call her a different name "Nitzy". This name bears no relation to her actual name at all, and if we call her her actual name she says "I am not x, I am Nitzy". I know that I did this a child, insisting that I was called Montgomery but I was older, about 4 when I went through this stage. Does anyone else's toddler do this? Is it best to play along or ignore?