Expecting baby No. 2? Experts say honesty about what's to come is the best way to help an older sibling prepare

There's a funny story told in Jennifer Thompson's family about how her older brother "welcomed" his baby sister to the fold.

"He made a sign that said, 'Devil Baby, $5' and tried to sell me," Thompson, now 37 and living in Groveland, Fla., tells Yahoo Life. "I'm not sure if I should be more offended that he thought I came straight from hell or that I was only worth $5."

But Thompson's big brother isn't the only kid who has thought of selling off their younger sibling: The transition from only child to older sibling can sometimes be a rocky one. All of a sudden the attention is divided and there's someone else in the house that seems to need Mom and Dad more. It's no surprise that older siblings can feel abandoned and forgotten when baby arrives, leading to resentment, behavioral issues and the occasional "Devil Baby" sign.

Actress Julia Stiles recently brought home her second baby, Arlo and shared her 4-year-old son Strummer's way of coping with the change on Instagram. Spoiler alert: Strummer didn't take it well, scrawling a face on the toilet tank — complete with brown paper cut-out beard — and a vaguely phallic drawing in red marker all over the seat cover.

In the candid post, Styles shared a sweet photo of baby Arlo's feet, along with a photo of Strummer's creation. "Scroll forward to see how my 4-year-old is taking it," she joked of Arlo's arrival.

Susan Groner is author of Parenting with Sanity and Joy: 101 Simple Strategies and host of The Parenting Mentor Sessions podcast. Groener says it's normal for older siblings to feel a bit overwhelmed by the arrival of a new baby, especially since they aren't always clear about the ways their day-to-day life will change until baby actually arrives.

"Kids are constantly getting messages that having a little brother or sister is going to be so amazing," says Groner. "We say things like, 'Aren’t you excited to be a big brother?' Then, when it turns out to be less great than they expected, that's when you can have some disappointment and resentment."

Little helper or little monster?

Julia Cziraki of Orlando, Fla., remembers the stress of bringing her toddler and new baby home from the hospital. "Our toddler started having a fit in the hospital room when he realized we were bringing the new baby home," she says. "He wanted to ride in a wheelchair down to the car like me. When he couldn't, he screamed the entire way out [of the hospital]."

"It was the dreaded toddler-kicking-in-the-car seat scenario," Cziraki adds. "This scene started my newborn crying and then I started crying. Then my husband started crying. We literally pulled away from the hospital and into a side parking lot where we all just sat there and cried."

Groner explains most parents don't know what going from one child to two will be like — so it's normal for them to struggle to make their children understand. "Kids see that other adults are excited about the new baby so they pick up on that," she says. "They think it'll be really cool and fun, but they don't know that a lot of things are going to change that they might not like very much."

Groner says when a new baby comes home, children will immediately notice changes in behavior or routine, like a parent needing to pause playtime to handle a crying baby or their own struggle to get a parent's attention when previously that attention was focused just on them. "This is when kids start to think that maybe if they start acting like the baby, they'll get attention like the baby does," she says.

Rachelle Freeman, a mother of two from Charlotte, N.C., says her 6-year-old daughter experienced bathroom regression — a sudden abandonment of previously-learned potty training practices — when her new sister came home from the hospital.

"She grabbed one of the baby's diapers, squatted and pooped right in it," Freeman recalls. "This happened a few times: When I asked her why she did it, she said she wanted to remember what wearing diapers was like."

"I offered to buy her diapers made for 6-year-olds and she quit that immediately," Freeman adds, "but not before pooping and peeing in her toy chest, which we ended up having to throw out."

Groner says sometimes these actions are a child's way of expressing their emotions.

"Depending on their age and vocabulary kids just might not have the words to describe how they're feeling about the baby," says Groner. "Instead, they just act out the emotions. They show us how they're feeling instead."

Setting expectations beforehand is crucial

Groner emphasizes that having an open conversation with a child about what it will be like when their little brother or sister arrives is crucial in minimizing the shock factor. To open this conversation, Groner suggests taking out a cell phone or family photo album and looking at pictures from when the sibling-to-be was a baby.

"You're giving them a window into what's to come when you show them what they were like as a baby: the good, the bad and the ugly," says Groner. "Show them photos of when they cried and you needed to pick them up or of feeding them as infants. Point out how tiny they were and how much they've grown. Tell them that their sibling is going to start out like that, too, and even though the baby will need you more than they do, it doesn’t mean you love them any less."

Groner also encourages parents to let their child guide them in how much they want to be involved in the new baby's care. Some kids may want to help, while others may not be so keen to assist. Either way is OK.

"I used to hate it when people would tell my daughter she would be 'mommy's little helper,'" says Groner. "I would just say, 'Sure, if she wants to be," because I think it's important to let your child have a choice in the matter."

Groner says parents should be honest with their child: The baby will cry and it might be annoying. Offer the child the opportunity to help soothe the baby or change a diaper, knowing that if they prefer to just play by themselves or do their own thing, that's OK, too.

Allowing a child to experience their feelings toward their new sibling is key. As an example, Groner shares that when her daughter was 2 and her son was 6 weeks old, her daughter asked if she could put her brother in the garbage pail.

"I said, 'You know, I think he would fit in there, but we're not going to do that,' and that was the end of the conversation," she says. "We don't need to make our kids feel bad about their feelings. We acknowledge them and move past them if they're not constructive."

Tips for once the baby is born

There's no "right" way to introduce a child to a new baby, but Groner suggests making the child a part of the action. "We put a photo of our daughter in our son's bassinet while he was still in the hospital and let her see that she was already a part of his life," says Groner. "It showed her that she was still special to us and that she was still a major part of our family."

Groner also says she brought her daughter to her final OB/GYN appointment before giving birth. "I told her that she could ask the doctor any questions she wanted to," says Groner. "I don't remember if she did, but I do remember that it made her feel important and valued."

Groner says uninterrupted one-on-one time between parents and the older child is essential. "Take 15 minutes every day to play with your child and give them your undivided attention — no phones," she says. "It doesn't have to be anything elaborate or planned. It could just be 15 minutes of snuggling or playing with a toy they like. Just total emotional connection."

Groner also suggests parents verbalize how important that time is to them, repeating that they are there for the child and that they love them.

To parents concerned about facilitating bonding between siblings, Groner says never fear. "Bonding will happen naturally," she says. "The more we try and push this stuff, the less fun and natural it feels. If your child wants to hold the baby, great. If not, that's fine, too."

"Children are adaptable and inherently curious," she adds. "As long as your child feels they're in a judgment-free, worry-free zone they'll feel more and more comfortable to explore what it's like in their new role."

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