In the UK the best thing to use is called Front Line, its only available from the vet but is really good, you can also get a can of spray for your house from the vets, you need to do every room.

yes frontline is the best thing and the vet can also do the tratment , i woudl also askt he vet as to how long you should keep the animals apart but i woudl think they willl all need treatment , its liek with headlice if your child comes home with even 1 the whoel family is meant to  be treated ,