I had a tough time finding the missing line. Hopefully, search engines will find this post and other readers who noticed the error will not have as much trouble as I.
Ivy Compton-Burnett: “Parents and Children”
Penguin edition, p. 248:
Nevill detached himself from Regan, as if this would aid his father’s view.
Nevill detached himself from Regan, as if this would aid his arms and laughed and whimpered alternately...
Correct text:
Nevill detached himself from Regan, as if this would aid his father’s view.
Fulbert came forward and picked him up, and he sat in his arms and laughed and whimpered alternately...