Preparing a Toddler for a New Baby
Medically reviewed by Dr. Emily Torres, PhD, CCC-SLP · Pediatric Speech-Language Pathologist
Content reviewed against published AAP, CDC, Zero to Three guidelines
Last reviewed:
Behavioral development varies greatly from child to child. If you have noticed preparing a toddler for a new baby, here is what you need to know.
The short answer
Adjusting to a new sibling is one of the biggest transitions a toddler will face, and some regression and behavioral changes are completely normal. Most toddlers need weeks to months to fully adjust, and their reactions can range from excitement to jealousy to temporary regression in skills they had mastered. With patience, consistent routines, and dedicated one-on-one time, most children settle into their new role as an older sibling.
Key takeaways
- Adjusting to a new sibling is one of the biggest transitions a toddler will face, and some regression and behavioral changes are completely normal. Most toddlers need weeks to months to fully adjust, and their reactions can range from excitement to jealousy to temporary regression in skills they had mastered. With patience, consistent routines, and dedicated one-on-one time, most children settle into their new role as an older sibling.
- Usually normal when: Your toddler has temporary regression in potty training, sleep, or speech around the time the new baby arrives
- Call your doctor if: Your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP, CDC, Zero to Three guidelines, adjusting to a new sibling is one of the biggest transitions a toddler will face, and some regression and behavioral changes are completely normal. Most toddlers need weeks to months to fully adjust, and their reactions can range from excitement to jealousy to temporary regression in skills they had mastered. With patience, consistent routines, and dedicated one-on-one time, most children settle into their new role as an older sibling. At 12-24 months, toddlers under two have limited understanding of what a new baby means. They may not grasp explanations about pregnancy, so focus on simple, concrete preparations like reading books about babies and practicing gentle touch with dolls. After the baby arrives, expect clingy behavior, sleep disruptions, or changes in eating, as your toddler senses the shift in attention. Maintaining their existing routine as closely as possible provides the most comfort during this transition. It is generally considered normal when your toddler has temporary regression in potty training, sleep, or speech around the time the new baby arrives. However, you should contact your pediatrician promptly if your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning.
Normal vs. Concerning
By Age
What to expect by age
12-24 months
Toddlers under two have limited understanding of what a new baby means. They may not grasp explanations about pregnancy, so focus on simple, concrete preparations like reading books about babies and practicing gentle touch with dolls. After the baby arrives, expect clingy behavior, sleep disruptions, or changes in eating, as your toddler senses the shift in attention. Maintaining their existing routine as closely as possible provides the most comfort during this transition.
24-36 months
Two-year-olds can understand more about what is happening but may still struggle with the reality of sharing their parents. Common reactions include demanding to be carried like a baby, reverting to diapers or a bottle, or acting out with hitting or tantrums. These are not signs of failure; they are expressions of big emotions your child does not yet have words for. Involving them in baby care tasks like fetching diapers or singing to the baby can help them feel included and important.
3-5 years
Preschoolers can be more involved in preparation and may feel excited about their role as a big sibling. However, they may also express jealousy more directly through words or behavior changes at preschool. Setting aside regular one-on-one time, even just 10-15 minutes a day, has a significant positive impact on adjustment. Acknowledging their feelings without judgment, such as saying "It is hard to share Mommy and that is okay," validates their experience and builds emotional resilience.
What to Tell Your Pediatrician
- Describe when you first noticed preparing a toddler for a new baby and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if regression or behavioral changes are still intensifying after 2-3 months rather than gradually improving.
- Mention if your toddler is repeatedly aggressive toward the baby despite consistent redirection and supervision.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Your toddler has temporary regression in potty training, sleep, or speech around the time the new baby arrives
- Your child alternates between affection toward the baby and ignoring or expressing frustration about the baby
- Your toddler is more clingy, demanding, or emotional than usual for several weeks after the baby comes home
- Your child occasionally says things like "send the baby back" or "I don't like the baby," which is an honest expression of their feelings
- Regression or behavioral changes are still intensifying after 2-3 months rather than gradually improving
- Your toddler is repeatedly aggressive toward the baby despite consistent redirection and supervision
- Your child seems persistently sad, withdrawn, or anxious in a way that is out of character and not improving
- You are feeling overwhelmed managing both children and need support or strategies from your pediatrician
- Your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning
- Your child shows signs of severe emotional distress such as refusing to eat, extreme sleep disturbance, or complete withdrawal from all activities for more than a few days
What You Can Do at Home
- Keep track of when you notice preparing a toddler for a new baby — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your toddler has temporary regression in potty training, sleep, or speech around the time the new baby arrives — this is generally within the range of normal.
- At 12-24 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Respond consistently and calmly to your baby's behavior. Maintain predictable daily routines.
- While monitoring at home, seek immediate care if your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning.
Related Resources
Frequently asked questions
Is preparing a toddler for a new baby normal?
When should I call the doctor about preparing a toddler for a new baby?
When is preparing a toddler for a new baby normal?
What causes preparing a toddler for a new baby?
What should I mention to my pediatrician about preparing a toddler for a new baby?
Is preparing a toddler for a new baby normal at 12-24 months?
Is preparing a toddler for a new baby normal at 24-36 months?
Should I go to the ER for preparing a toddler for a new baby?
Does preparing a toddler for a new baby go away on its own?
References
- [1]American Academy of Pediatrics. Preparing Your Family for a New Baby. HealthyChildren.org. AAP
- [2]Centers for Disease Control and Prevention. Positive Parenting Tips: Toddlers (1-2 years). CDC
- [3]Zero to Three. Preparing Your Child for a New Sibling. Zero to Three
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Preparing a Toddler for a New Baby.
Things to mention
- Describe when you first noticed preparing a toddler for a new baby and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if regression or behavioral changes are still intensifying after 2-3 months rather than gradually improving.
- Mention if your toddler is repeatedly aggressive toward the baby despite consistent redirection and supervision.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Regression or behavioral changes are still intensifying after 2-3 months rather than gradually improving
- Your toddler is repeatedly aggressive toward the baby despite consistent redirection and supervision
- Your child seems persistently sad, withdrawn, or anxious in a way that is out of character and not improving
Urgent signs to report immediately
- Your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning
- Your child shows signs of severe emotional distress such as refusing to eat, extreme sleep disturbance, or complete withdrawal from all activities for more than a few days
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of preparing a toddler for a new baby are normal. Talk to your pediatrician if your toddler has hurt the baby or made a serious attempt to harm the baby, requiring immediate safety planning.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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