Sounds like you'll have your hands full there! I was never one for baby talk with my girls and my eldest could speak clearly from the moment she started talking. Although now she's 19 I often can't understand her, because she's become lazy with her words. She claims it's just how the Aussies speak (we're from England originally), but I can understand Aussies. 🤔
I think she decided she wanted her independence the moment she hit her teens and that's when things got really rough. She can run rings round me, convince me black is white and it will take me a day to realise I've been had and she just got exactly what she wanted from me. She's left home now, which I must admit has reduced stress levels.