There seems to be an assumption now that children are given two forenames. I read lots of references to “the second name”. I know that two has been the commonest number for many years. Many people now also have double-barrelled surnames. It used to be mostly the aristocracy who had several names, though my mother and her sisters (very humble) had three each. My brothers had one each and so do two of my children. I thought it a bit special as it was less usual and their single names were quite long. Have all your grandchildren, like mine, got two names?
I've always used my middle name. Why, because my first is the same as my mother's. No, I wasn't named after her but her two best friends. Over the last ten years I've become used to going by my first name because, after being made redundant years ago, forms always ask for first name. I usually put first name but underline my middle name for emphasis but no-one picks up that that might be the one I go by.
My dad had four first names! William Reginald Tyldesley Cornthwaite and then his surname! I loved it. He explained that we should have been double barrelled - Cornthwaite-******** but never bothered. I really fancied a double barrelled name.