My friend has a chunky 2 and half year old. As she doesn't drive, she needs a new buggy for him. However, pretty much all the buggies seem to have a max weight of 15kg, and he's now over that.
Why is this? It's not that uncommon for parents to need buggies for older toddlers surely?
I know five years ago my boy was in a buggy until past three, because we didn't drive and his legs wouldn't cope with walking everywhere.
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Hello,
We've noticed this thread is quite old and some of the product recommendations are a little out of date. We've spent weeks speaking to parents and testing out pushchairs and buggies. Read our reviews of see which lightweight buggy was crowned best. [Spoiler alert is has a 25kg weight limit].
Hope that helps! 
MNHQ