Hi mommy, I think you should get your son checked by a developmental pediatrician because there might be some underlying issues with your son kaya hindi pa siya nakakapag-salita in sentences. For cases like that, usually the child will require therapy eh. I highly suggest that you get him assessed ASAP kasi the earlier the intervention, mas madaling ma-rerectify yung issue. The same case happened with my daughter, she’s also four but she’s been undergoing through therapy since she was two years old.