Weird breathing pattern..

I have noticed Leah grunting here and there. Maybe two times in the past week - it sort of sounds like she is pushing to poop. Today she was doing it, but she was sitting in her carseat and I was driving so I couldn't really pay attention. Then tonight she was sitting on my lap before bed and I really could see it. It's like she holds her breath for a few seconds and then almost pushes it out with a grunt...then breathes a little faster to catch up...then holds it again. It is so strange. I'm going to go listen to her in her sleep later to see if she is doing it then too. I don't think she is ALWAYS doing this - but things aren't exactly calm and quiet around these parts.

She hasn't seemed out of breath or anything. She doesn't seem sick at all, no stuffy nose or fever. She's still sleeping the same. So I dunno - it's just weird.

She has a ped appt next week but I may call and see if we can bump it up.

Has anyone experienced this?