It only took a year, but we did it! My daughter and I finished reading all 8 books in the Anne of Green Gables series. I gave her the first book last year, in early June, for her 9th birthday, and I was determined that we should finish before her 10th, as more literary gifts await her. Thankfully, we met the deadline with over a week to spare. I had visions of us staying up late in the night before her birthday in an effort to reach my self-imposed deadline.
No, we did not read Anne every night. My younger daughter is too young for Anne, so if I only had time for joint reading, Anne didn't make the cut. And there were times when we needed a break, a palate cleanser, when my daughter was in the mood for picture books (which she still loves, much to my delight), or something else entirely.
At times it was tough going. The language is flowery and old-fashioned. The middle books tend to be gossipy stories about people Anne interacts with and less about Anne herself. And the final book, set during World War I, has lots of arcane (to my 9-year-old) references to military personnel, politicians, and battles.
But it was worth it. There's a kind of satisfaction in finishing a series. The other series we have done this with are the Betsy-Tacy books, the Ramona books (multiple times, but a much quicker read) and the All-of-a-Kind Family books (ditto, and sadly, the last book was quite disappointing).
I know lots of people have done the same with Harry Potter. What other series have you read aloud to your children in their entirety? How long did it take you?