There are many causes for weight gain of this kind but thankfully only one answer - EAT LESS AND EXERCISE MORE for what is gained can also be easily lost. Get out and get some fresh air and a relaxing walk or go indoors but do something.
To allow children to eat what they like is tantamount to neglect. To supervise their eating, allowing some sweets and treats, is caring. To make sure they get the one hour of physical activity a day is kind; but to ignore it is cruel. Why? Because not only their health and well-being suffers but they are also left open to bullying and finding normal activities difficult. Their very school life can be affected because of tiredness and sluggishness and a lack of concentration. If parents are obese then they too have to take control over their family's eating because it is a very important area gone out of control that needs to be harnessed in without delay. If a child age 11 has diabetes, take 10 years off their life is the stark fact health warning.
There is advice aplenty at GP's and amazing amounts of support out there but over eating must be faced head on.
Lord, we know that obesity has become the accepted norm in many societies. But, it is not acceptable to eat more than the mind and body requires because of the seriously detrimental effects on health and future health. I ask that those affected will come to You in prayer about it so that You can help them take control of it and change lifestyles for the better. You will give self control and promote the encouragement and determination to lower body weight to a healthy level. Help them get it all out onto a plate with You and deal with the real issue/s bit by bit.Thank You. You can do whatever you need to do through Christ Phil 4.Amen.