Waltham – Mrs. Aileen E. (Decker) Clark, of Waltham, died, Thursday, May 8, 2008 at Maristhill Nursing Home, Waltham. She was 86. Born in Brooklyn, New York, Mrs. Clark, a daughter of the late Walter and Zulika (Goss) Decker, she had lived in Waltham for more than 55 years. She had for many years been a foster mother for Catholic Charities of the Archdiocese of Boston and had also been an activities director at several area nursing homes. During World War II, Mrs. Clark served with the United States Marine Corps. The wife of the late William H. Clark, she leaves her children, Elizabeth A. 'Betsy' Clark-Miceli of Sandwich, Thomas G. Clark of Lawrence, Mary A. Gilberto of Weston, Karen M. Clark of North Reading and Stephen A. Clark of Manchester, New Hampshire; 6 grandchildren, 1 great-grandchild and many nieces and nephews. Mrs. Clark was also the mother of the late William H. Clark, Jr. and sister of the late Genevieve Conception and Doris Page. Relatives and friends are invited to attend the Funeral at 9:30 a.m. Tuesday from The Joyce Funeral Home, 245 Main Street (Rte. 20), Waltham followed by a Funeral Mass in Saint Jude Church, 147 Main Street, Waltham at 10:30 a.m. Burial will be in Calvary Cemetery, Waltham. Visiting hours are Monday from 4 to 8 p.m. Memorial donations may be made to Catholic Charities, 75 Kneeland Street, 8th Fl., Boston, MA 02111 or to Dana Farber Cancer Institute, 44 Binney Street, Boston, MA 02115.