The short answer
Developmental concerns at 7–9 months can include losing a skill, persistent one-sided movement, or changes in communication or interaction. In England, a health visitor review is offered at 9–12 months, but you can raise concerns with your GP or health visitor sooner. One observation alone does not diagnose a condition.
In this guide · 11 sections
Keep in mind
- Milestone lists help you track development; they are not diagnostic tests.
- Losing a skill your baby previously used is a reason to seek an assessment promptly.
- Around nine months, sitting, response to name, varied sounds, and interaction with objects are considered together.
- Not crawling at nine months is not, by itself, a developmental red flag.
What does a “red flag” mean?
The term “red flag” can sound alarming. Here it does not mean your baby has a diagnosis; it means an observation may deserve a closer look from a health professional. One baby may master one movement before another, and that can be ordinary variation. What matters is the overall direction of development, continued progress, and whether you have other concerns.
In England, families are offered a 9–12-month health and development review, including discussion of language, learning and any concerns. A review or questionnaire is not a diagnosis; it helps you and the health visitor decide whether further support or assessment is needed.
Should a seven-month-old do everything a nine-month-old does?
It would not be fair to expect a seven-month-old to demonstrate everything listed for nine months. Sitting, grasping objects, communicating through sounds, and responding to people can change considerably over those two months. Consider your baby’s exact age and what they have already been able to do.
Babies develop at different rates across the seventh to ninth months. During the 9–12-month review, your health visitor can discuss movement, communication, interaction and any skills you are concerned about. If a skill has been lost or you are worried before the review, contact your GP or health visitor rather than waiting.
When a previously learned skill disappears
Pay attention if your baby has stopped making sounds they used to make often, uses one hand much less than before, or shows a lasting change in eye contact and interaction. Losing an acquired skill is different from simply learning a new skill later than another baby.
Tiredness, illness, or a change in surroundings can temporarily affect behaviour. Even so, it is best to discuss a clear loss of skills promptly with your GP or health visitor rather than trying to explain it away yourself.
What to watch for in sitting and movement
Around nine months, many babies can sit without support. If your baby repeatedly tips sideways while sitting, clearly uses one arm or leg differently, or shows a movement change that concerns you, asking for an assessment makes sense. Look at movement across different moments, not just one brief observation.
Crawling styles and timing vary, and not crawling in one particular way does not by itself establish a developmental problem. Give your baby safe floor space to move rather than forcing a movement or using a baby walker to hurry development.
Why responding to their name and making sounds matter
Notice how your baby responds to familiar voices, faces and play across different everyday situations. A single missed response while tired or absorbed in a toy is different from a persistent change in interaction or communication.
If you are concerned about hearing, very limited vocal sounds, or a clear decline in social communication, discuss it with your GP or health visitor. Those observations do not point to a single diagnosis on their own; hearing and developmental assessment may be appropriate.
If you are worried about several areas
If you notice concerns in several areas, such as movement, communication and interaction, share them together with your GP or health visitor. A clinician can consider your baby’s history and decide whether a developmental assessment or referral is appropriate.
Your GP or health visitor will consider your baby’s history, examination, and developmental progress. If needed, they may recommend a standardised developmental screening or refer you to a specialist. Screening looks for the need for further assessment; it is not itself a diagnosis.
What can you do today?
Over the next few days, observe your baby during natural play. What happens when you say their name? How do they use each hand when you offer a toy? What movements do they try on the floor? Brief notes about when you first noticed a concern can help at an appointment.
You do not need to test your baby over and over to make a skill appear. Face-to-face conversation, songs, suitable toys, and safe floor play provide enjoyable, natural opportunities both for development and for observation.
When should you talk with your paediatrician?
Arrange a conversation without unnecessary delay if a skill clearly disappears, movements consistently favour one side, or communication concerns persist. You can raise a concern even if it is difficult to descote.
For babies born prematurely, an assessment may also consider corrected age. Tell your GP or health visitor your baby’s gestational age at birth, health history, and observations. If there is a sudden change in consciousness, a seizure, or trouble breathing, seek emergency assistance rather than waiting for a routine visit.
When to seek support
Some signs need emergency help; other concerns can be discussed with your child’s healthcare team.
- Clear loss of a previously learned movement, sound or interaction skill.
- Persistent one-sided movement or a marked change in communication or interaction.
- Concerns across more than one area, or continuing carer concern: contact your GP or health visitor.
Sources used for this guide
- NHS — Your baby’s health and development reviews
- NHS — When to use NHS 111 for urgent advice about babies and children under 5
English editorial review:
The English text and regional guidance have been checked editorially. This is not an individual clinical assessment.
Luluna provides general parenting information. It does not diagnose conditions or replace your child’s healthcare professional.
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