I'm sorry I don't quite see what you mean. Do you mean live donation? Or donation once donor is dead? If live donation then only bone marrow and 1 kidney can be given (I don't think a doctor would consider taking a lung from anyone still alive).There was a case some years back where a father wanted to donate a kidney to each of his 2 sons and then go on to dialysis himself but the consultant wouldn't go for it. If you mean donation after death then you've got 2 kidneys, a liver or possibly 2 can be got for 2 children from 1 adult liver, a heart, lungs (or heart/lungs),and more minor things such as eyes pancreas.