Final answer:
The 13 month-old unable to walk requires further follow-up to assess their developmental milestones, as children are typically expected to start walking by 12 months and should at least be pulling themselves up and walking with help at this age.
Step-by-step explanation:
The nurse in a well-child clinic must evaluate children who may require further follow-up based on developmental milestones. Among the toddlers listed, the one that requires further follow-up is:
- A 13 month-old unable to walk. While children typically start walking by 12 months, there is a range of normal development, and some children may not walk until 15 or 18 months. However, by 13 months, it is expected that a toddler should at least be pulling themselves up and walking with help. The potential delay in walking might warrant further assessment to rule out any developmental issues.
The other toddlers mentioned seem to be meeting general developmental milestones for their age. A 20 month-old using 2 and 3 word sentences is showing normal language development; a 24 month-old who cries during examination may exhibit stranger anxiety, which is normal; and a 30 month-old drinking from a sip cup might not be of concern as they may just prefer it over open cups but should still be able to drink from a cup without frequent spills.