"I'm afraid they're becoming really selfish," my friend said.

"My two girls fight over everything, from what movie they're going to watch, to who gets the Wii first. I don't know what to do about it."

Children's squabbles are part of parenting, for sure. Sometimes they're a sign of tired bodies, surging hormones or natural orneriness. But other times, they're a flashing beacon that something more is at work: selfishness.

And what better time to help our children uproot selfishness than Thanksgiving?

Our culture offers so much, materially, that it's easy for our children -- and for us, too — to take for granted how much we really have.  We stop noticing all that we do have in our endless quest for what we don't have.  We forget to consider what our lives would be like without the gifts — people, talents, possessions, opportunities-- that already have been given to us.

The antidote? Gratitude. Researchers have found that people who cultivate the habit of gratitude reap all sorts of benefits, from better health to greater happiness to stronger relationships.

For adolescents, gratitude is a vital piece not only for character formation but also for day-to-day perspective. A recent study by researchers at several leading universities reports that children who show more gratitude experience less envy and depression. Conversely, children who rank higher on materialism experience less happiness, and struggle more with grades and contentment.

How to Save Your Family Through the Practice of Gratitude

Back to the squabbling sisters. What will help them change course? How can parents cultivate gratitude instead of envy and discontent?

First, set limits: When selfishness is a problem, parents need to limit their children's constant access to entertainment, diversions, trendy possessions, and fleeting "wants" -- at least for a time. Materialism grows where material possessions abound and when there are few limits on when and how often they will be enjoyed.

It's not that these possessions -- amazing electronic advances like the iPad or elementary school fads like Silly Bandz -- are bad in themselves. They are not. But our children's vision quickly becomes nearsighted, focused only on what's in front of their own noses. And then they want more of it. And they don't want others to have it, lest they feel like they've "lost" something.  Multiply that attitude by a dozen beloved possessions, and you've got the makings of a selfish child. So, pare down and limit.

Second, start a daily exercise in which whining children (or parents) write down things they are thankful for.  Researchers have found that the simple act of keeping a "gratitude journal" increases happiness and wellbeing. When we have to stop and think about what we are grateful for, and write it down daily, we reduce the tendency to take our things, talents and friendships for granted. We appreciate the good in our lives more deeply.

Third, encourage humility. Robert Emmons, one of the premier researchers on happiness and gratitude, emphasizes that it's not enough to be grateful, in the abstract, for the good things in our lives. We need to be grateful to someone.  We need to look outside ourselves — and acknowledge our dependency on others -- particularly God -- for the source of the goodness in our lives.

Make it a daily practice to thank God for his goodness and blessings, and to thank those around us for their kindness, generosity and friendship.

And on this Thanksgiving, let's begin our feast with a humble acknowledgement of the good in our lives and a vow that we will always remember that all good flows from the hands of the One who created us - and that He is worthy of our thanks and praise.

Visit Crosswalk's Thanksgiving Facebook page at www.facebook.com/iAmThankful.