I found the furry ring in the toy box so I assume Fric took it downstairs at some point and I just picked it up along with all the other toys and didn’t even notice.
Had a “Be still my heart” moment this morning when I looked into the pen first thing and all four of the pups rushed (OK, waddled at quadrupedal rather than larval speed) to the edge of the box to greet me.
Tomorrow I plan to dismantle the pen and put up the playpen so they’ll have more room to stagger around.