Caustic soda?

I don't know that I've ever had much success with *any* chemical
solution.

Or did you teach her how to use a proper plunger to pull all the cr@p
back up into the sink?

Nope, not that either, it will probably be a strip down of all the
plumbing from the trap back as far as necessary (all removable
plastic) and to clean it out properly. ;-)

It should be funny because whilst she seems able to shovel a flattened
animal off the public highway, she gags at the content of a well used
drain. ;-)

She knows what she has put down there!

I'm not sure she does ...

Cheers, T i m

The problem is getting any chemical actually in contact with the blockage.