I know this was probably decided before I joined, but I want to put my two cents out there anyway. I think these two characters need separate pages.
Kris is the protagonist of Night of the Living Dummy. Lindy is the secondary protagonist in the second half of the book and a minor antagonist in the first 60%.
Even though the book is written in third person, it's third person LIMITED, from Kris's perspective. We explore Kris' jealousy of Lindy, and Kris' feelings about the living dummy. Kris brings Mr. Wood to life. Kris is terrorized by Mr. Wood. Lindy being terrorized by Mr. Wood in the end is similar to Sarah's sister being there at the end of Night of the Living Dummy 2. That doesn't make her a protagonist. Kris is the main character of this book.
Lindy is a minor antagonist because she bullies Kris by making her think the dummies are alive for more than 50% of the book (I think I was at 63% on my Kindle when Kris read the magic words to actually bring Mr. Wood alive -- the rest of the book was all Lindy).
The twins have different physical appearances, different personalities, and different roles. I think they need different pages on the Wiki.
I would be happy to create two separate pages for these characters (I enjoy writing about characters), but wanted to get permission/thoughts first.
I feel like there would be too much repetition between pages. The characters are very closely related, which leads me to doubt people would actually want to view separate articles. I'm not a big fan of creating new pages that don't really provide new traffic or new info.
Side note, can Lindy really be considered a bully? I'm not sure she would fit in among the other folks in that category. She's competitive and a bit of a jerk (almost exclusively in the first half), but she doesn't seem to be a bully. And, from what I can see, the competitiveness goes both ways. Kris says Lindy's ventriloquism is dumb, but then she sees that the dummy is actually Lindy popular, so she pulls a flip-flop and demands her own dummy.
I consider Lindy a bully. She constantly picks on Kris ("Gotcha again!"), and it's not mutual. Kris calls her names and they are competitive, sure, but it's not to the same extent. Lindy goes to the same lengths Mickey Holmes, Sticks, and other bullies have gone. I mean, she emptied out her parents' fridge all over the floor. ;)