5:13am....really?

Avery needs a lesson in how to sleep in...she thinks that 5:13am is a good wake up time. And now at 6:55am Olivia is starting to sing in her crib, which means she is ready to start the day, how come when it was Brad's turn with the girls yesterday Avery didn't get up until 6am and Olivia didn't stir until closer to 8am. What gives? Clearly they just want to spend more time with me...that's it right?