nap time help.

I'm a SAHM. I do home daycare. My LO is 16 months. Her napping schedule was a little like this. 9AM- 10:30-11, wake up eat lunch and nap at 12-12:30 till 2:30 when the rest of the daycare kids napped. & than wanted another nap at 4:30-5pm and go to bed at 8 or 9pm. She sleeps all night, but now she isn't wanting the nap after lunch. The most crucial nap I want her to be taking! Should I just stick out her crying and fussing when she wants the 9AM nap? Or what? I'm at a loss. Second day in a row she hasn't napped and it's not really not ideal!