Brief Answer:
Observe for few days, in most of the babies improves with time

Detailed Answer:
Hi

Thanks for asking on 'Ask A Doctor' platform
I have gone through the query and do understand your concern.
Speech delay is quite common nowadays and is mainly due to nuclear family, working parents and Use of electronic gadgets.
I won't get overly worried for mild change in gait. Involvement of one leg only rules out any developmental disorder. I would suggest you to check if there is any tenderness in ankle joint due to unnoticed trauma causing difficulty in walking. In most of the babies it is transient in nature due to pain from unnoticed trauma. You can try giving paracetamol ( an analgesic) to relieve pain if any. Observe for the pattern of walk and if it persists longer please visit a pediatrician for evaluation.

I hope this helps.
Please let me know if you have any more doubts.
Regards

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