He’s getting more curious as he’s growing older and starting to understand a little more things. My LO was also like that when she was a bit older. I try to make sure there aren’t any distractions and any loud noises at home when she’s taking her nap so she doesn’t feel like she’s being left out of anything. It helps her sleep a little longer when it’s very quiet at home and the room must be dark too. Maybe you can try that and see if there are any changes to his sleeping routine