ds is 4.5 months and had been on fairly good routine for a few weeks with am nap usually around 8.45-10, lunchtime 12-2 if lucky and cat nap bjust before 5. he now gets grumpy at 12 but wont go down. couple of times have just fed him and he is happy till about 2 when he sleeps maybe 2 hours. have others found activity time extending at this stage too and should i move to just 2 naps?