Her welcome back included a video message from President Obama.
Roberts had to get the transplant after doctors diagnosed her with the rare condition myelodysplastic syndromes, or MDS.
MDS is a group of disorders that cause the bone marrow to produce an inadequate number of helathy red blood cells, white blood cells and platelets. Cells in the bone marrow that make blood cells don't mature, don't make enough blood cells, or make defective cells, according to the Mayo clinic.
The disease can develop after exposure to certain chemicals or radiation. Roberts was treated for breast cancer five years ago and has said the treatment likely caused the disease.