Yes, you can give your 6-month-old son Laxaday if he is constipated. It is recommended to start with a glycerin suppository for children, which usually takes effect in about 15 minutes. If the constipation persists, you can give him about 1/4 to 1/2 dose of Lax-A-Day per day, dissolved in milk or water. It's important to also increase his hydration by offering more liquids such as milk or water.