Check Vinted - I’m on a Facebook baby wearing UK group that’s really good. Maybe a lennylamb preschool and you could do a back carry?
@Sinead she'll only walk for so long and where we are going there are lots of hills, also thinking of the airport
For a 3 year old you're likely to need a preschool carrier rather than a toddler carrier. They tend to be rather costly so if it's just to be used on a holiday you might want to consider hiring from a sling library.
@Abby I've just been looking at hiring and it makes more sense at £15 for 2 weeks.
For the airport we found pulling our 3 yo on a trunkie super helpful especially since we got a baby to carry too.
is she not good at walking? we went on holiday with our 3 year old last year, when he was 2 and a half, and he basically walked everywhere, and we got a cheap easy foldable pram off of facebook marketplace for £10 to take on holiday for if we went on a longer walk and didn’t cause any hassle at all xx