It's all the mother's fault is a very, very old way of thinking on speech problems. I'm 72, have stuttered since I was 3 and my poor mom blamed herself for most of my younger years. Why? Because speech pathologists told her it was her fault. Too much this, not enough that. It wasn't until I was old enough to choose my own therapists that I realised it was all BS and I just drew the worst spin on the genetics wheel. We had a good cry together over me telling her it was never her fault.