trying to drop the first nap

Well we have been having quite the time with Caleigh's first nap.  Two Sundays ago Caleigh missed her first nap because of church (like usual).  On Monday we went to a consignment sale (lots of cute things for Andrew this summer!) in the morning and she missed her nap.  On Tuesday I put her down in the morning for her nap and she talked/played in her crib from 9:30-10:45 so she didn't sleep.  On Wednesday mornings I go to a women's bible study at our church and so I let Caleigh play at childcare (instead of napping) and she did fine.  On Sunday and Monday our afternoon naps were fine - 2.5 hours or so.  Then we started to hit some trouble on Tuesday and Wednesday as they started decreasing to 2 hours.  She didn't take a morning nap all last week and her afternoon nap got progressively shorter until the final straw - on Sunday after missing her morning nap she only slept for 1 hour!!!  So in the span of a week she went from sleeping 3.5-4 hours a day to only sleeping 1 hour a day.  That was not cutting it.  Her afternoon naps were never affected by her taking a morning nap - provided I woke her up by 10:45 and so I guess she just wasn't ready to drop it.  The only thing is she is 16 months - I am wondering how much longer she will nap in the AM.  I will definitely drop it by 18 months at the latest, before Andrew gets here... Live and learn.