Would depend on the material the piping is made from
It's not the toilet, there's a blockage in the pipes some where after the drain pipe from the toilet joins up with the drain pipe from the tub.You're going to need to have the pipe snaked.
More information needed. Is it visible, is it underground, is is plastic, is it metal pipe - -
WeldBrazeTap and plugCut out and install a union
The most nessecary tools needed to fix a clogged sink are a plunger to extract the material clogging the sink and a sewer snake to hook and extract the debris.
First isolate the area that needs repair and drain it. If it is only a hole in a PVC water pipe Get a piece of pipe the same size and cut it in half along the length. Clean both the pool pipe with the hole in it and the new piece of pipe with primer then put PVC solvent cement on both the patch and the pipe and hold it firmly in place until the solvent cement has set, To save you having to hold it in place you can get one or two hose clamps to do the job for you. If a large section of pipe needs replacement, cut out the damaged pipe and replace with similar pipe and connectors.
Partial blockage. Snake the drain.
She watched the water spiral down the drain.The doctor needs to drain the fluid.The drain is blocked.
If it is galv. pipe there could be a small hole on threads. You would have to replace pipe.
If the pipe is in good enough shape you can weld over the hole, BUT If there is one small hole rusted in the system it is a good sign the pipe is rotted. There will be many other holes soon. There are probably more holes than you know about. You will probably have to have an exhaust shop put in a new pipe for you.
Cut out the old piping and caulk a new cast iron bell and spigot with lead and oakum and test
They sell rubber sleeves that are used to join PVC and galvenized lined. Putting this over the leak and placing the hose clamp over the damaged are should solve your problem for now.
Put Copper Sulfate in the drain. It will kill the roots and they will eventually break off and go down the drain. This isn't an immediate fix.