Maybe she's just had Lenka on the brain. She's got large sections of quite a few of her songs memorized, and in particular, she's been hung up on this little diddy:
Though she knows the words (at least to the chorus), this was the version she was singing when Tom overheard her earlier today:
"My heart hmm hmm hmm. My heart hmm hmm hmm."
Trying to be helpful, Tom suggested, "My heart skips a beat."
He was met with a resounding, and prolonged, "NOOooooo."
This was followed by, "My heart doesn't skip a beat. My heart doesn't skip a beat."
And that's how she's proceeded to sing it for the remainder of the day.
She is young and healthy, after all. Perhaps it's a commentary on her (no doubt) perfect resting heart rate. We should all be so lucky.