Reuses second nap

Sydney

For the past couple of weeks my 9mo does not want to take his second nap. He goes to bed at 8 and wakes up at 7. He takes a 1.5 hr nap at10ish and used to take a 1.5 hr nap at 230ish. Now he just plays or whimpers. Do you think it might just be his brain because of all the new things happening? Will he go back to 2 naps soon? How do I get him to not be such a cranky pants if he refuses to sleep or if he does how can I get him to not want to sleep at 9 when he sleeps late? Any advice would be welcome!