I'm sorry, Jackie. I hope you got that nap today after all! I've been lucky for this past week because DH is off of work. I'll be back to tearing my hair out tomorrow I'm sure.
Catharine's comments on timing are helpful. I'm always tempted to pull up the nap to before noon because I know my dd is tired (eg she got up at 4:50 am today!!!! Talk about my resettling routine backfiring.) You know, it can't hurt to play with the later time to see if you get more consistency. Worst case scenario is you still don't get the nap. However, I do think you're lucky that Carmela is still getting naps more days than not. The problem is you having to fear it and get frustrated each day! That's the part I want to get over. Whether or not Karina takes a nap, I just want peace of mind!
If I keep having problems I'll try the later time too and let you know. My problem is I've tried it before (not even by purpose or choice, but it's hard to get the nap in before 12:30 as that's when I pick up my son from preschool). So if I put her down close to 1, she doesn't have time to settle to sleep if she doesn't go right down. If I put her down closer to 11, she'll usually get in a nap, even if it takes her 2 hrs to get to sleep! Neither way is ideal, just haven't gotten to the best place yet.