Dying guinea pigs and kids

[unlikelychump]

I think one of our guinea pigs might be on his way out.
We've only had him a month and they are our first pets. Kids have been so desperate for them and spent so much time with them both. Really love them.
They are 22 months old, rehomed. This one has a couple of lumps and bumps and is booked in for the vet on Friday anyway as a check up. He seems to have stopped poo-ing or is doing tiny little ones.
So sad.

This is going to be so awful for the kids. 11, 10 and 8. Am I going to get them to school tomorrow?

Hay racks are generally not recommended (based on the various guinea pig Facebook groups I'm in). That's because they can get their heads caught in them. Piles of hay work well and lots of hay makes them less likely to get teeth issues.