When can I put things eg. Litter tray/toys in bonding pen?

Just wondering, because my poor buns look really bored stuck in the pen would like to put a box or something in there for them to jump on/nibble for something to do. Will be enlarging the pen either tonight or tomorrow, it's currently 4x2x2 NIC cubes, was going to make it 4x3x2, is this ok?

How long have they been in it for?

Since Saturday morning... But all is calm and snuggly now

If all is calm you can introduce the litter tray
Or something to do, but keep close eye on them, and if it upsets them take it away again...

You'll know when your buns are ready