I'll add that, unlike what your parent wrote, asset reuse will be minimal, in adventure games, one of the reward for solving puzzles is unlocking access to new locations and thus new art.
In this case, they may reuse some of the sprites for the main characters (default animations). Most of the animations are custom and can't be reused.
Likewise for the voice acting (I'd expect them to start from scratch here, the mood of the games may be a bit different).