I win the lottery every night (unfortunately only in my dreams!)
I think you should only tell the people you really trust IF you have to tell anyone at all. I cannot imagine any of my friends would ask me how I financed a new purchase or extension or house move. They may speculate and even joke about the lottery but I do not think I would tell.
I hope you and your family enjoy your winnings and all it will help you all accomplish . Let people wonder. Keep your knowledge to yourself. I think it will make your life easier in the long term!
Good luck and enjoy. I am off the corner shop to buy my ticket .