British actress Natasha Richardson suffered a fatal brain injury while skiing in Canada in March. She died March 18 at 45.
"I'm still getting extraordinary condolence letters from American people that's deeply touching," E! News quoted Neeson as saying on "GMA" Wednesday.
He said he and his sons --13-year-old Daniel and 12-year-old Micheal -- are "taking each day as it comes" and doing the best they can despite their grief.
Neeson -- whose film credits include "Taken," "Batman Begins" and "Schindler's List" -- is currently on U.S. screens in limited release in "Five Minutes of Heave," opposite his fellow Northern Irishman, James Nesbitt.