At first, your new baby won’t pose much of a threat to your firstborn’s precious possessions, jealously guarded space, and self-appointed status as head honcho. But once your baby starts to crawl (and snatch stuff), expect the turf wars to begin in earnest. For one thing, toddlers and young preschoolers are practically defined by their need to claim every last thing they see as “mine!” and babies aren’t exactly known for respecting property rights. For another, all the attention your newborn gets for being, well, a newborn, may leave your numero uno feeling like he’s been demoted to second-class citizen. What’s more, if your older one is still pretty young — as in under three — he’s still probably not fully getting this whole sharing concept you’re always touting. Especially when it comes to sharing with the space-invading grab machine you call his little brother. So how can you help your children grow up (mostly) rivalry-free for the long haul? Read on

Show them how to share. Taking turns and sharing prized possessions can be tough, even for grown-ups — and like just about all social skills, these key ones must be learned. So, first off, get ready to teach through your generous example. Model the big-hearted behavior you’d like to (one day) see in your kids: Offer both of them a piece of your muffin, a turn at your computer, a chance to pick out what’s for dinner. Let them catch you and Dad sharing (“there’s only one pretzel left, Honey — let’s split it”), inviting someone with just two items to go ahead of you on the supermarket line, giving up your seat for an elderly woman on the bus. Play games that encourage turn-taking, like rolling a ball, and suggest activities that encourage a group effort, like drawing on an extra-large piece of paper.

Keep them real. Your expectations, that is. It’s not realistic to expect your older child to share everything with his little bro, and it’s not really fair either. Rights are a two-way street, and if you’re always asking your eldest child to relinquish his in favor of his sib’s because “he’s just a baby,” resentment’s sure to brew. Letting your older child know that certain belongings are his and his alone will help him feel less possessive — and, if you’re lucky, more inclined to share the rest of his stuff. Make sure you follow through with protecting those rights too (instead of always giving the baby his way). A good time for your older son to play with his exclusive treasures — and to play in a pest-free space: baby’s nap. Did you catch your firstborn in the act of sharing, or taking turns with his sibling? Pour on the praise. Did you catch him instead shoving his brother away from his block project? Criticize his behavior, not him.

Time turn-taking. Tired of being The Enforcer of taking turns? Turn to a timer. Objective and unequivocal, a timer can take uncertainty out of the turn-taking equation, encouraging cooperation and sharing. Use the timer to set limits on how long each sibling can play with a certain toy before turning it over to the other (of course, each should receive the same time limit). It may take a few tries before your little ones learn to respect the buzzer — but once they start to see that what goes around (their sib’s turn) comes around (their turn), you’ll face fewer fights over communal property.

Be an equal-opportunity praiser. Sure, your little one is making developmental leaps and bounds. But as you celebrate those accomplishments (as you should), make sure you don’t take your older child’s skill sets for granted. That — if you remember back to your own sibling days — can fuel sibling rivalry (as in “Mom likes you better!”). If you find yourself praising your baby’s newfound ability to grasp his spoon, be sure to crow over your preschooler’s agility when it comes to pouring the milk.

Give refereeing a rest. If you’re always quick to step into a sibling conflict, they’ll never learn how to resolve one on their own (and remember, sibling play is great social practice). With a little guidance, even young siblings can work together to find ways to share. When you spy a tug of war over that plastic hammer, wait a minute to see if they can figure out a compromise. That’s clearly not happening? Step in calmly and ask your older child how he thinks he might stop the struggle. He just might pick up on your impartial, problem-solving approach (and your respect for his big-kid abilities) and come up with a suggestion — like using a different tool while his baby sib swings the hammer, or setting the timer so they can both take a turn. (If he doesn’t come up with this, a little power of suggestion goes a long way, Mom.)

Open the vent. Little siblings can be irritating, and so can sharing everything you used to have all to yourself (including your mom and dad). Let your older child know that it’s okay to vent the angry feelings everyone feels sometimes. Just keep your perspective (and cool) as he does (he’s not up to self-editing yet). When he says, “I hate Braden — I wish he would go away forever!” he’s just expressing his very normal angry feelings about a sibling who knocked over the block tower he just spent all morning toiling over. So skip the “What a terrible thing to say — you don’t mean that” (because of course he doesn’t mean it, not literally). Instead, help him feel understood. Empathize: “You’re really angry at Braden because he knocked down your tower. You worked really hard on that.” Don’t try to explain away the baby’s behavior (“he doesn’t know any better”) because that won’t help him feel heard — and it won’t bring back his tower either. The key is for him to know that his emotions are valid and justified, so he can let the rest of his anger go.

But don’t let things get physical. No matter the precipitating offense, be clear that venting anger by hurting another person is unacceptable. Let your child know in no uncertain terms that if he hurts his brother he’ll have a time-out. Be straightforward, not emotional, about following through, but be evenhanded when it comes to discipline. If your baby is the aggressor — he’s pulling his brother’s hair or biting him — remove him from the scene and take him to the crib to chill. Showing your firstborn that you don’t play favorites will help him respect the rules (and you).