antonio dot nunes

I'm trying desperately to figure out what this new word means. I have this fantasy that it's Antonio's new special word for me, as if to say "I recognize that you're not actually one of my parents so I will refrain from referring to you as 'dada' ... but you're around pretty often and I like you an awful lot, so here's a name for you!" I also realize that he's been saying it to the shower curtain quite a bit which leads me to consider three possible scenarios:

1. "na-na" is his new word for me and his address of the shower curtain as such was a misfire.
2. "na-na" is just some random new di-syllabic he's spitting out whenever it strikes his fancy.
3. "na-na" is his new word for both me and the shower curtain, who he now recognizes as significant quasi-parental figures in his life.

The boy does like to spend a lot of time in the bathtub, after all ...