Sakura sleeps a lot too.  It's an off and on all day thing.  We get up about 7:45 and by 9:30 we are at work and she is back to sleep.  I was worried that she was sleeping too much and that something was wrong but this has eased my thoughts!  At work she only is awake if she has to potty about or someone walked in and so the can pay attention to her.  
