Can I know why my 4 mths old baby keep yawning? He will always wake up 30min duration for his nap himself without being disturbed. Not enough sleep?

He is tired. Maybe u can try these few ways. 1. While sitting down on ur sofa, place ur baby on ur chest area. Like putting baby on carrier, facing u. Pat his buttocks gently to slp. 2. Place baby on his bed lying on his side. Put a small pillow or bolster in between his legs. Let him hug a small pillow or bolster den pat him to slp. I think e 1st method may work for u better!