Mum has moved them from her box to under the washstand. I think she has more room to spread out as the kittens were almost filling the box.
I got up this morning to kitties wandering all over the bedroom, and yes, they are starting to eat solids. If you look closely enough, you see tiny wet footprints where they have walked through the water bowls.
The best toy of all? My feet! They lick them, bite them, then try to climb up my legs!