Hi Natalie
I have spoken to two people who may have known your relatives but unfortunately neither could recall a family by the name of Morris or shine any light on why the cottage got the name O'oo.
The proper name is Hillside Cottage, although our friend says that when she was a girl it was referred to as Scudder's Cottage, and I'm pleased to say that it still exists. Undoubtedly it is internally substantially different from when our respective families lived there as then it was divided in two with my family (the Scudders) living in the right hand side as you look at the building. Fortuitously, from the outside at least, it hasn't changed greatly being, I think, a listed building and probably one of the last Essex weatherboard cottages left in the area. The division of the property would explain the overlapping dates you mention. I have some reasonably current photographs of the outside and if you would like to PM me your email I'll find them and send them to you.
Unfortunately my great grandfather, Stephen Scudder, didn't own the property - as so many in the area he was a farm worker and I doubt that he was ever in the position to buy his own house. I seem to recall my grandmother saying that it was rented - I have some notes from conversations when she was alive and if you will bear with me I'll see if there is anything in them that will help and email it to you.