"She's been a rock for him. Even when she can't be with him physically, she'll call to try to life (sic) his spirits and make sure he's eating," said a source. "(They) feel that renewing their vows is a perfect idea. They're grateful to have each other," the source added. The "Wall Street" star, who is currently undergoing chemotherapy and radiation treatment for throat cancer following a diagnosis last month, married Zeta-Jones in 2000. Douglas, 66, and Zeta-Jones, 41, have two children together -- 10-year-old son Dylan and seven-year-old daughter Carys.