Well every one want to increase his/her height, but 60-80% of your height is determined genetically so it is advised to marry tall guys and girls.
1.Inside your body your height increases due to growth hormones, so in case of deficiency of growth hormones, dwarfism occurs so get your hormones level tested at correct time, if not done you cannot do anything to increase your height if your epiphysis has been fused with metaphysis of bone.
2.Some how it is also effected by quality of life and standard of living.
3. You might be suffering from Achondroplasia.
4. If you are suffering from hypothyroidism than also it will lead to shorten your height, so get it tested.
5. Stress in children can also retard their height will lead to psychogenic dwarfism.
So take care of all these points and increase the height of your children, yes you can do one more thing try these exercises and increase height to some extent, watch video below
If nothing works wearing high heel shoes can add few centimeters to your height.