Yours, Mine & Ours 2005 on netflix

Admiral Frank Beardsley returns to New London to run the Coast Guard Academy, his last stop before a probable promotion to head the Guard. A widower with eight children, he runs a loving but tight ship, with charts and salutes. The kids long for a permanent home. Helen North is a free spirit, a designer whose ten children live in loving chaos, with occasional group hugs. Helen and Frank, high school sweethearts, reconnect at a reunion, and it’s love at first re-sighting. They marry on the spot. Then the problems start as two sets of kids, the free spirits and the disciplined preppies, must live together. The warring factions agree to work together to end the marriage.