Final answer:
We are unable to provide an answer regarding the color of the big wooden swing painted by Uncle Weldon as the specific detail is not included in the provided passages and pertains to the book 'Rain Reign' by Ann M. Martin.
Step-by-step explanation:
The question does not pertain to any specific passage provided in the references and seems to be related to a different text. Unfortunately, without access to the specific context the question is referencing, it is not possible to provide an accurate answer regarding the color Uncle Weldon paints the big wooden swing.
In such a scenario, it is always best to directly refer to the source material of the question, in this case, the book 'Rain Reign' by Ann M. Martin, to find the specific detail asked about. However, since we do not have the specific passage from 'Rain Reign' where this detail is mentioned, we are unable to provide an answer to this question.