Don't make baby foods available so he's forced to make choices from the family meal. Infant food should be discontinued by 10 months. Besides being expensive, it doesn't provide enough energy or variety for a 3-year-old. Although it would be wise to have him visit a pediatric dentist to rule out any oral pain, if he can eat cookies, he can at least eat soft table foods.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.