Police have only described Mr Spedding as a person of interest who has been assisting them with their inquiries.

Now that is an interesting description.  Not used before.

I read that couple have grandchildren living at their house as well.

That maze sounds weird. The police took away a mattress and a computer from a unit that man ( Mr Spedding) rents also. Rents a house, has a pawn/ appliance repair business and rents a unit ( not sure if it is a residential unit or business).

The police had received a tip off to look at that man.

If malicious..........I feel for the couple..

Heard on the news that "police have not ruled out Mr Spedding as a person of interest".

The man in question went to the house for wash mach repairs ( a few days before William and his family arrived). I guess the police look closely at everyone that had any contact recently with the people that lived there.

The unit is above the business premises.

They have custody of 3 grandchildren, no idea why but it isn't unusual. Many grandparents step up when parents fail to parent..

 I was reading what his daughter-in-law said in an interview, she refered to her father-in-law and his wife. The father-in-law grandchildren. He has five adult children.

Thanks for the info about the unit.

I Would be interested to know more about the childs family.Some strange  situation there too.Due  to 'complex legal situation' the parents cannot be named or speak publicly and in the paper it made reference to the family's mysterious past and the childs troubled upbringing....that interested me it sounded like they were in witness protection or something 

Little William does not live with his biological mother. She has other children.

It is not likely that Docs identify children in foster care.