Hey mate,
Unfortuanately, I have no idea! I'm with you one this one I'm afraid. When I asked my best friend about her two, she said one went to 1 day sleep at about 14 months, while the other hung onto it until about 19 months. I think it depends on what time they get up. If they are early risers, it takes a little longer to drop one sleep. My DD gets up at 530 on the dot every morning...so she is always back in bed for at least an hour by 8/830. Sometimes she refuses this sleep and has a good one about lunch time, and I think she wants to drop it, but then the next day reverts back to two sleeps.
I wouldn't force the issue, just go with the flow. Maybe it'll all happen in her own time. Unless it's inconvenient for work or other (for yo I mean), I'd let it take it's course...
Hope this helps!
Julesy
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