Travelling with kids can be both challenging and rewarding. Indians are very tolerant of children so you can take them almost anywhere without restriction, and they always help break the ice with strangers.
However the main problem with children, especially small children, is their extra vulnerability. Even more than their parents, they need protection from the sun, unsafe drinking water, heat and unfamiliar food. All that chilli in particular may be a problem, even with older kids, if they’re not used to it. Remember too, that diarrhoea, perhaps just a nuisance to you, could be dangerous for a child: rehydration salts are vital if your child goes down with it. Make sure too, if possible, that your child is aware of the dangers of rabies; keep children away from animals and consider a rabies jab.
For babies, nappies (diapers) are available in most large towns at similar prices to the West, but it’s worth taking an additional pack in case of emergencies, and bringing sachets of Calpol or similar, which aren’t readily available in India. And if your baby is on powdered milk, it might be an idea to bring some of that: you can certainly get it in India, but it may not taste the same. Dried baby food could also be worth taking – any café or chai-wallah should be able to supply you with boiled water.
For touring, hiking or walking, child-carrier backpacks are ideal; some even come with mosquito nets these days. As for luggage, bring as little as possible so you can manage the kids more easily. If your child is small enough, a fold-up buggy is also well worth packing, even if you no longer use a buggy at home, as kids tire so easily in the heat. If you want to cut down on long train or bus journeys by flying, remember that children under 2 travel for ten percent of the adult fare, and under-12s for half price.