You all have shown quite a lot of sensitivity for the relations between the literary characters. The mother's unfaithfulness has obviously bothered you the most!
Does this mean that you also appreciate faithfulness that much in your private life?
As for the mother's looks, you can read on the page 24:"Mother was a small person who smelt nice." Only one mentioning, so no wonder you couldn't recall.
Now let's move to the 5th, the last task in this cluster.
As you know, Christopher has a row of behavioral problems, described as autistic.
Just to name some of them: not talking to people for a long time, not liking being touched, screaming, refusing food, especially if it is the "wrong" colour ( yellow or brown in Christopher's case) ...
WHAT WOULD GO ON WITH YOU, YOUR TEACHERS AND CHRISTOPHER IF HE SPENT A MORNING WITH YOUR CLASS?
How would you approach him? Would he be able to endure with so many people in one room? ... Just unleash your imagination. OK?

The film on autism, Rainman; starring Tom Cruise and Dustin Hoffman
We must watch it once in the near future!