Found this in a longer interview about White Countess, but this is the bit I was most interested it -- it confirms what I have wondered/suspected for a while about the names of their children.

"Natasha Richardson, who stars in the new -- and final -- Merchant Ivory film ''The White Countess," has inherited much from her mother, Vanessa Redgrave.
"There's the beauty -- fine features, wide, doe eyes -- and husky voice that combine to give her a delicate, refined presence.
"There's the private life lived as part of a theater couple: Richardson, 42, is married to Liam Neeson, with whom she has two young sons, 10-year-old Micheal (''it's written in the Gaelic way, and he was named after Michael Collins and Michael Redgrave, my grandfather," says Richardson) and 9-year-old Daniel (''named after Father Daniel Berrigan," who officiated at the marriage of Richardson and Neeson)."

FYI: Father Berrigan was a consultant (and had a one-word speaking part!) in The Mission, and he and Liam apparently despised & avoided each other until Liam found out Berrigan was one of the organizers of the prayer vigil at Long Kesh prison during the hunger strike in which ten men died protesting their treatment by the British authorities. He sought Berrigan out and they became friends -- I think I read somewhere (maybe the horrible biography) that Liam even served as "altar boy" when Fr. Berrigan celebrated Mass for the cast & crew. -- rtk