Memories of The Letter, the Witch, and the Ring

Some remembrances from our archives of The Letter, the Witch, and the Ring (1976):
Donna Pedaci was tagged to name seven favorite children's books and enters the following at #6 n her list:

This is the third in a series that features Lewis Barnavelt and his best friend Rose Rita. Lewis lives with his uncle Jonathon, who is a wizard. Next-door-neighbor Mrs. Zimmerman is a friendly witch. This book is mostly about Rose Rita, who travels to Michigan with Mrs. Zimmerman to see the farm she (Mrs. Zimmerman) just inherited from her cousin Oley. Soon they find themselves involved in a mystery involving a magic ring and a long held grudge.

The San Diego Momma herself harkens back to childhood to this distant memory:

...cradling a leaning tower of checked-out books under my chin, willing them not to fall, as I made my way past the McDonald’s and over two bridges back home; or swallowing the peppermint taste of excitement as I willed my legs to stop bouncing long enough to read the back of John Bellairs’ The Letter, The Witch and the Ring.