This is a sweet song. It reference to her voice it sounds to me like she has been a little slack with her voice care and vocal exercises. Like all muscles the voice and breathing apparatus require exercise and rest to remain on point. It's not enough to just sing a lot or rest a lot. She can still still, she's just gotten a little complacent that's all and it can be heard in te lack of diaphragm support when she tries to project and transition through her registers..