It’s time. You’ve sat your little one down to tell him the big news: He’s about to have a new brother or sister. You want to make it as easy as possible for him to adjust. Maybe he’ll accept the news without a hitch—or maybe he’ll feel his world is coming to an end.

In a way, his world is coming to an end, and everyone in the family needs to understand that. “The dynamics in the family with one child are unique,” says Helga Cohen, a licensed marriage and family counselor and head of counseling at a private school in San Francisco. “The first-born will get all the love, affection and care, meaning quality time with either one or both parents, and takes this undivided attention for granted because he/she has not experienced a different family setting. Suddenly having siblings in family brings competition into the family system.”

Sibling rivalry can start from the minute you share the news with your child, and it’s important to remedy it as soon as possible to make sure your kids not only get along, but also love each other as much as you love them.

Break the ice early on. Prepare your child for the possibility of a younger sibling joining the family, even if it’s not certain yet. The sooner you talk to him about his upcoming role as big brother, the easier the process may become. There are many children’s books available to help him understand what it means to expect a new baby in the family, and showing him his own baby pictures may help him create a connection from the very beginning. Include him in activities like helping to choose the new baby’s name and rubbing Mom’s belly to feel the baby kick.

Show that you understand his feelings. Kids react to a new sibling differently depending on the age gap. If your first child is still quite young, he may have more trouble understanding how you could love him the same as ever now that this new babe has dropped into your life. “Children who are younger than 4 years are in the process of developing a strong sense of self and others,” Cohen says. “In those early years, children are quite self-centered and are just beginning to develop the ability to understand the feelings of others.”

If there is a more sizable age difference, your oldest may not feel threatened as much as overwhelmed by the responsibilities that come with a new baby sibling. He may respond better if you show him how important he is as a role model and protector for the baby. Teach him how to hold the baby properly if it’s safe for him to do so, or how to give a warm backrub to promote positive touch between them.

Don’t place blame. To hold onto his “one and only” status, your child may act out and try to seek your attention through negative actions, like throwing temper tantrums or acting like a baby himself. He may also become more clingy or possessive, attempting to regain your lost love and affection. Be sure not to blame your new baby for the time you can’t spend with your first-born. If he’s upset you’re missing your routine afternoon walk, don’t say it’s because the baby’s sleeping; use an alternate reason, like waiting until after snack time. Saying things like “Why can’t you understand?” is also a big no-no. The more he thinks the baby is taking you away from him both physically and emotionally, the more he’ll want to get the little stranger out of his house completely!

Demonstrate through your own actions and words. Your boy is going to follow your lead, so make sure you are always setting a good example. If he thinks throwing a beach ball at his new sibling the way he does with his friends is okay, quickly fix the situation by showing him safe ways to play. Hover around the two when they’re interacting so you’re there the instant your little boy acts out or might hurt the baby, and be ready to show him what to do next time. Protect your newborn as well by constantly teaching your oldest how to treat the helpless babe.

Don’t spare the affection. “Parents need to find a way to give the undivided attention and affection that they were able to share with their first-born child in a different format, triggering the same feelings of love, affection, care and trust.” says Cohen. If your oldest doesn’t feel safe or loved with you before and after the baby comes, it will be harder for him to finally accept the bundle of joy without resentment. Make the effort to say extra “I love you”s or take time to read a bedtime story to him, without the baby.

Remember that no matter the age gap between your children, you are setting the tone and example for your oldest to react to his new family member. Reassuring him through words and actions that his loving, secure world won’t disappear with this new addition is key to a future full of laughter and affection between all family members. Breathe deep and smile—be there for your first-born through this period of adjustment. That’s all he wants.

Do you need more perspective on sibling rivalry? Try out this article, "5 Things Parents Can Do to Squash Sibling Rivalry."