Washington, D.C. ? Vice President Dick Cheney’s daughter Mary delivered an 8-pound, 6-ounce baby boy on Wednesday, the first child for her and her female partner of 15 years, Heather Poe.

Samuel David Cheney was born at 9:46 a.m. at Sibley Hospital in Washington, the vice president’s office announced. Vice President Cheney and his wife, Lynne, paid a visit to their new – and sixth – grandchild a few hours later.

Mary Cheney announced in December that she and Poe had decided to start a family. Her decision to become pregnant and raise a child with Poe was criticized in some conservative circles.