Can we talk about her voice ?

Becky says that her voice is naturally high-pitched and that this is her real voice, but I have been in a lot of lives of hers and at some point in the middle (like 1:10 or so) her voice starts getting lower and she "forgets" to speak in that voice or use certain expressions. And I believe it's 100% fake, because I sometimes fake accents online and mid-way through I get tired and "forget". And whenever someone questions her and her voice she gets so defensive. What's y'all's opinions ?