04/05/2007 AT 08:20 AM EDT
Mary Cheney's first child is due next month – and it'll be a boy, her father Dick revealed Wednesday.
"I'm delighted I'm about to be a grandparent for the sixth time," the Vice President, 66, told ABC News Radio, according to The Washington Post'
s Reliable Source
column. "I'm looking forward to the arrival of a new grandson."
Cheney's press secretary confirmed in December
that Mary, 38, and her partner, Heather Poe, 45, were expecting a baby.
Later that month, President Bush, who opposes gay marriage, told PEOPLE
: "I think Mary is going to be a loving soul to her child. And I'm happy for her."
Mary Cheney, vice president for consumer advocacy at AOL, met Poe, a former UPS manager, when they both played ice hockey during college in Colorado. Poe has been renovating the couple's suburban Virginia home since they moved there after the 2004 reelection campaign.
During that campaign, Mary said she disagreed with President Bush's stance on same-sex marriage and told PEOPLE, "I am in favor of legalized same-sex marriage."
Asked about his daughter and her partner's legal standing in his interview yesterday, Vice President Cheney said: "I think each state ought to have the capacity to decide how they want to handle those issues," the Reliable Source reports.
"And I obviously think it's important for us as a society to be tolerant and respectful of whatever arrangements people enter into."