You asked

When is my child too old for a buggy?

There is no definite right or wrong answer to this question. It depends on your child’s size and personality. If your child is very active and tired of sitting still then there is no problem taking away the buggy and letting them walk. Just be careful that you don’t bring them on any long walks without a buggy – you’ll find yourself acting as a carrier towards to end! Of course if your child no longer fits into a conventional buggy then it’s safe to say they are too old and should be walking without the buggy.
Around 4 years of age (or about 80lbs) is the age most children will either be too heavy or too tall for a buggy. Most single running buggies have a maximum safe limit of around 75lbs. Having a child over this weight in a buggy can be dangerous and the buggy will become unbalanced and could easily tip over.

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