An opinionated 89-year-old Toronto woman received a royal surprise in the mail after sending a letter to Prince William.

The day before Prince William announced his engagement to Kate Middleton, Florrie Kay decided to write a letter to His Royal Highness, announcing that she didn't feel it was right that he had lived with Middleton before getting married.

"I saw she had no ring. I said in Toronto when we go around with somebody for a year or more, you get a friendship ring or a wristwatch. What's with you?" said Kay.

Prince William announced his engagement the next day, but Kay had already sent him the letter.

"When he gave her the ring, I thought oh my God he's going to get this letter," she said.

Less than three weeks later, a response from St. James Palace arrived via. first class mail.

Kay said she was shaking when she opened the letter, wondering if officials were going to arrest her.

Instead, the letter read:

"Dear Mrs. Kay, Prince William has asked me to thank you for your letter in which you suggest suitable ways an unmarried couple may demonstrate their mutual affection.

It was kind of you to take the trouble to write as you did. As I am sure that you are now aware, His Royal Highness is to marry Miss Catherine Middleton on 29th April 2011 in Westminster Abbey, and he has accordingly presented her with an engagement ring; the ring that had belonged to his mother, Diana, Princess of Wales.

Prince William has asked me to send you his best wishes."

The letter is signed by the prince's personal secretary, Mrs. Claudia Holloway.

Kay also received a congratulatory note from Buckingham Palace on the occasion of her 60th wedding anniversary.

She says she hopes it's not the last time that she hears from the Prince.

With files from CTV Toronto's Andria Case.