How to Prepare Your Toddler for a New Baby: What the Research Says

The arrival of a new baby is one of the
most significant transitions a toddler
will face — and one that parents often
approach with more anxiety than necessary,
or less preparation than would help.

The research on toddlers and new siblings
is specific and actionable. This article
covers what the evidence shows about
how toddlers understand and respond
to a new baby, what preparation actually
helps, and what the practices are that
make the transition smoother for everyone.

What Toddlers Understand About
a New Baby

Before discussing preparation,
it helps to understand what toddlers
actually comprehend about a new sibling —
because the mismatch between what
parents explain and what toddlers
can understand is one of the most
common preparation mistakes.

Research on toddler cognitive development
finds that children under three have
very limited capacity to understand
abstract future events. The concept
of a baby who is currently invisible —
inside a parent’s body — who will
arrive at some unspecified future
point and permanently change the
family structure is genuinely beyond
the cognitive reach of most toddlers.

This does not mean preparation
is useless. It means that effective
preparation for toddlers is concrete,
repeated, and close to the event —
not abstract, detailed, and delivered
months in advance.

Research by Laurie Kramer at the
University of Illinois on sibling
relationship quality finds that
the quality of preparation —
specifically the degree to which
the older child is given realistic
information, involved in the process,
and supported through the transition —
significantly predicts sibling
relationship quality in the
months following the birth.

What Preparation Helps

Concrete, honest information
close to the birth. Research
on toddlers and new siblings
finds that preparation is
most effective in the final
weeks of pregnancy rather
than months in advance —
because the toddler’s time
perception makes distant
future events essentially meaningless.

Simple, concrete, repeated
information works best:
“There is a baby growing
in Mummy’s tummy. When
the baby comes out, they
will live with us. Babies
cry a lot and need a lot
of help. You will be the
big brother/sister.”

Books about new babies.
Research on bibliotherapy
and children’s transitions
finds that picture books
about new siblings —
read repeatedly in the
weeks before the birth —
help toddlers build a
concrete, positive narrative
about what is coming.
Books that show babies
crying, sleeping, and
needing a lot of attention —
rather than only showing
babies as cute companions —
are more effective at
setting realistic expectations.

Involvement in preparation.
Research on sibling transition
and older child adjustment
finds that toddlers who
are involved in concrete
preparation tasks —
helping choose the baby’s
name, helping set up
the baby’s room,
choosing a gift for
the baby to bring home —
show better initial
adjustment than those
who are not involved.
Involvement creates
a sense of agency
and positive anticipation
rather than passive
displacement.

Honest acknowledgment
of what will change.
Research on toddler
adjustment to new siblings
finds that children
who are given honest,
age-appropriate information
about what will be
different — “the baby
will need a lot of
Mummy’s attention,”
“there will be times
when I can’t play
with you right away” —
show better adjustment
than those for whom
the changes arrive
as unexpected disruptions.

Protecting the toddler’s
special relationship
with each parent.
Research on sibling
relationship quality
and parental behavior
finds that toddlers
who continue to have
regular one-on-one
time with each parent
after the baby arrives
show better adjustment
than those whose
individual time with
parents is completely
displaced by the
baby’s needs.
Scheduling and protecting
this time — even briefly —
is one of the most
effective post-birth interventions.

What Typically Happens After the Birth

Research on toddlers’ responses
to a new sibling identifies
several common patterns
that parents should expect:

Regression. Research consistently
finds that toddlers often
regress following the birth
of a sibling — returning
to earlier behaviors including
bedwetting, baby talk,
thumb-sucking, and increased
clinginess. Research by
Judy Dunn at Cambridge
on sibling relationships
finds this regression
is nearly universal
and typically resolves
within a few weeks
to months. It is best
met with warmth and
patience rather than
correction or shame.

Increased bids for attention.
Research on toddler behavior
following a new sibling
finds that increased
attention-seeking —
including acting out,
increased demands,
and testing limits —
is extremely common
and reflects the
toddler’s accurate
perception that a
competitor for parental
attention has arrived.
The most effective
response is proactive
positive attention
rather than reactive
response to acting out.

Ambivalence about the baby.
Research on sibling
relationships in the
first year finds that
toddlers typically
show both genuine
affection and genuine
aggression toward
the new baby —
often in close succession.
This ambivalence is
normal and should
be expected. Both
feelings deserve
acknowledgment:
“Sometimes you love
the baby and sometimes
you wish they weren’t here.
Both feelings are okay.”

Faster adjustment than expected.
Research by Dunn on
sibling relationships
in the first year
finds that most toddlers
show significant positive
adjustment within
the first few months —
developing genuine
affection, interest,
and playful interaction
with the baby
more quickly than
parents typically anticipate.

What Does Not Help

Overpromising what the
baby will be like.
“You’ll have a new
best friend to play with!” —
this sets expectations
that a newborn cannot
meet. Research on
toddler adjustment
finds that realistic
preparation — including
the honest information
that babies cry a
lot, sleep a lot,
and cannot play for
a long time — produces
better adjustment than
overly positive framing.

Asking the toddler to
suppress their feelings
about the baby.
“You have to be gentle,”
“you’re the big one now,”
“the baby needs you
to be grown up” —
these messages ask
toddlers to perform
a maturity they do
not have and to
suppress feelings
that are valid.
Research finds that
acknowledging both
positive and negative
feelings about the
baby produces better
adjustment than requiring
only positive expression.

Completely displacing
the toddler’s routines.
Research on toddler
adjustment to new
siblings finds that
maintaining as many
of the toddler’s
existing routines
as possible — bedtime
rituals, mealtimes,
special activities —
significantly supports adjustment.

Try This This Week

Practice 1 — The Big Kid Special
What it is: A new,
toddler-specific privilege
or activity that is
explicitly connected
to being the older child —
giving the toddler
a genuine benefit
of their new role
rather than only
experiencing it as loss.

How to do it: Introduce
one thing that is
specifically available
to the older child
and not the baby:
A special bedtime story
that is “too grown-up for babies.”
A special snack that
“babies can’t have yet.”
A special activity
with a parent that
is “just for big kids.”

Name it explicitly:
“This is your special
[thing] — because
you’re the big one.”

Why it works: Research
on sibling adjustment
finds that toddlers
who experience genuine
benefits of their
older-child status —
not only the demands
of being “the big one” —
show better adjustment
and more positive
attitudes toward
the baby than those
for whom older-child
status is presented
only as responsibility.

Practice 2 — The Baby Feelings Book
What it is: A simple,
homemade book that
your toddler creates —
before or after the birth —
that gives them a
safe, contained space
to express all their
feelings about the
new baby.

How to do it: With
your toddler, create
a simple book with
one feeling per page:
“Sometimes I love the baby.”
“Sometimes I feel angry.”
“Sometimes I feel sad.”
“Sometimes I feel happy.”
“All my feelings are okay.”

Draw or find pictures
together. Read it
regularly — particularly
during difficult moments.

Why it works: Research
on emotional expression
and sibling adjustment
finds that toddlers
who are given explicit
permission to feel
ambivalent about a
new sibling — and
a safe container
for those feelings —
show better adjustment
than those whose
negative feelings
are suppressed or shamed.
The Baby Feelings Book
gives the ambivalence
a home.

Practice 3 — The One-on-One Anchor
What it is: A brief,
daily, protected one-on-one
time with the toddler —
scheduled and maintained
through the chaos
of the newborn period —
that communicates that
their relationship
with each parent
is not displaced
by the baby’s arrival.

How to do it: Choose
a brief daily window —
even fifteen minutes —
that belongs entirely
to the toddler.
During this time:
The baby is with
the other parent
or sleeping.
Your attention is
entirely the toddler’s.
The toddler chooses the activity.
No phone. No interruptions.

Name it: “This is
our special time —
just for you and me.”

Why it works: Research
on parental one-on-one
time and sibling
adjustment consistently
finds that toddlers
who maintain regular,
predictable individual
time with each parent
show significantly
better adjustment
to a new sibling
than those whose
individual time
is completely displaced
by the baby’s needs.

The Bottom Line

Preparing a toddler
for a new baby is
not about finding
the perfect words
or the perfect book.
It is about honest,
concrete, repeated
information; genuine
involvement in the
process; realistic
expectations about
what is coming;
and the protected
individual time
that communicates,
through every session,
that the toddler
is still loved and
still central.

The research is
reassuring on
one more point:
most toddlers adjust.
The first weeks
are typically the
hardest, and the
trajectory from
there is generally
upward — toward
the sibling relationship
that, research finds,
becomes one of
the most significant
and most enduring
of a person’s life.

Sources

Kramer, L., & Ramsburg, D. (2002).
Advice given to parents
on welcoming a second child.
Family Relations, 51(2),
122–134.

Dunn, J., & Kendrick, C. (1982).
Siblings: Love, Envy and
Understanding. Harvard University Press.

Teti, D. M., & Ablard, K. E. (1989).
Security of attachment and
infant-sibling relationships.
Child Development, 60(6),
1519–1528.

Volling, B. L. (2012).
Family transitions following
the birth of a sibling.
Current Directions in
Psychological Science,
21(2), 65–69.