K.C.
Hi L.!
We ran into a similar problem with our daughter when she was about the same age. I found that consistency is the key. We started putting her down for the night a half hour earlier and her naps were at the same time every day. If that meant that I had to rearrange our day because it was nap time then I did. Also, it wasn't long after that she gave up her morning nap so your little one may be telling you he's getting ready to drop that nap. Come up with a plan and stick to it. We also made sure that the routine every night was basically the same, bath, book, brush teeth, bed. The first few nights she cried but every night it was less and less until none at all and we had our wonderful sleeper back! Good luck!