I can understand the little girls not being allowed to play in the front yard, it is in the realms of possibility that people could ask them questions and journalists have been known to take photos of children and get interviews from children etc.
The windows I think may be precaution at night. perhaps you can see in. I said I would walk up and find out about those plates, I am capable of doing that, and would engage GBC in conversation if the situation was right, the little girls though are another matter.
I have always thought the "bus stop" sighting was strange. I have come up with a scenario though that I would like to get some opinions on:
Allison is expecting GBC to be home when she arrives on the Thursday evening, but instead NBC has been sent. He tells Allison that it is all over, the business is in deep trouble, the marriage is not working and Gerard wants a divorce and settlement. Allison is angry about NBC confronting her about these issues, about her husband not being a home (he was supposed to be looking after the children but took them to his parents home and drove his father back to his Brookfield home to wait for Allison). A full on row erupts, then calms a little and Allison prepares to drop Nigel home. In her car on the way they have another big row, NBC hits her and kills her. He then wanders aimlessly, calls GBC and he tells his father to wait at the bus stop. GBC driving his own car, picks up his father at the bus stop and they drive back to Allison car. The body is moved from the drivers seat to either the passenger seat or another car, probably the passenger or back seat and they then drive and dispose of the body. They then return to Brookfield and whatever happens after.
Perhaps someone else has another idea or can refine mine, it just fits in with some of the things we know are fact