United Airlines is changing course after four years, announcing that effective Feb. 15, families with children ages two or younger will be able to board the plane before other passengers. The policy change reverses one made in April 2012 that forced families to board with everybody else. At the time, the airline company said the move was aimed at simplifying the boarding process by reducing the number of boarding groups.

Sandra Pineau-Boddison, United's senior vice president of customers, says the policy shift is part of an effort to be more attentive to passengers' needs - a result of losing so many of them after they made the initial change.

"It takes a little bit of the stress out of the travel situation," she said, according to Consumerist. "Some things are just the right thing to do."

Family boarding policies vary from airline to airline, with some allowing families to skip in front of everyone, while others only allow families to board after first class and elite passengers have settled in.

Such policies have also been a prime source of contention for airlines and its customers, reported Chicago Tribune. On one hand, the airlines want passengers to board as quickly as possible. But on the other hand, airlines also want to reward high-paying customers by letting them board early. Furthermore, airlines are selling priority boarding directly to passengers or via credit card partnerships. Those who have such tickets gets to place their bags in the overhead bin, while those who don't usually have to check their bags at the gate.

The policies for other major U.S. airlines regarding family boarding are:

Alaska Airlines:  Families with children under 2 can board before first class and elite customers.

American Airlines: Families with children can board before first class and elite members upon request only, though the age is at the discretion of the gate agent.

Delta Air Lines: Families with car seats or strollers can board before first class and elite members.

Frontier Airlines: Families with children under 3 can board early.

Hawaiian Airlines: Families with children under 2 can board before first class and elite members.

JetBlue: Pre-boarding is available for families with kids 2 and younger, but only after elite members and passengers in premium seats.

Southwest: The airline allows families with children under 6 to board during Family Boarding, after "Group A" has boarded.

Virgin America: Families can board early if they're travelling with children under 5.

Spirit Airlines: Families are allowed on after passengers who paid extra to board early and those who purchased space for a carry-on bag in the overhead bin.