What about 15-month-old boy's speech development?

Speech development expectations for a 15-month-old boy span quite a wide range. At this age:

Understanding (receptive language): Babies typically understand simple instructions ("get the ball," "wave bye-bye"), recognize familiar objects and family members by name, and understand the meaning of "no."

Expression (expressive language): An average 15-month-old can use 3 to 10 meaningful words. These are usually everyday words heard frequently, like "mom," "dad," "water," "ball," "food," "no." Some babies use more than 20 words while others use just a few — both are considered normal.

Sounds and gestures: Along with meaningful words, lots of syllable repetition like "aga," "dada," "mama," animal sound imitations, pointing, head shaking, and waving are important parts of communication.

Red flags (require pediatrician and/or child development specialist evaluation):

• Not using any words at all
• No response to any sound or their name
• Lack of social communication gestures like pointing or eye contact
• Lost sounds they made at 12 months (babbling)

General pediatric consensus suggests that fewer than 10 meaningful words by 18 months is often temporary, but regular monitoring is important.