Being fair about her prejudices has never been my mother's strong point! However, reading your comment I realise I have just taken her presumption that it was a Catholic-thing rather than an education-thing as fact. Her learning to write was during WW2, so a touch later than you describe. I wonder when the educationalists started to shift this belief in the necessity of righthanded handwiting? And why it existed in the first place?
Re: Religion