What is the reason why children speak unclearly?

Patient's question:

Age
Detailed medical condition and purpose of consultation: Difficulty speaking clearly.
Duration and onset of this illness: Started from hours ago, initially not paid attention, now noticed that many of her words are pronounced unclearly, very anxious.

Doctor's answer:

Hello: It may be caused by an abnormally short frenulum, and it can be resolved by surgical resection.