Translation:Ceri Lingo and Dewi Lingo's mouse is brown.
Is there any way to distingish between “Ceri Lingo and Dewi Lingo’s mouse” and “Ceri Lingo’s mouse and Dewi Lingo”?
You could put a comma either side of a Dewi Lingo, perhaps. That would then indicate that both the mouse and Dewi are brown. Or else just use clearer phrasing.
Thanks. Come to think of it, English is ambiguous in that respect, too, if you turn the order around and leave out the Oxford comma: "Ceri Lingo and Dewi Lingo's mouse" = "[Ceri Lingo and Dewi Lingo]'s mouse/Ceri Lingo and [Dewi Lingo's mouse]".