A yellow hard hat sits tipped over the top of a big amber numeral, painted in loose watercolour with the brush marks still showing. A claw hammer leans against the other side, its wooden handle warm against the cream paper, and a few loose screws are scattered across the upper corners as though someone emptied a pocket. Along the foot of the card runs a black and yellow hazard stripe, the one hard-edged graphic on an otherwise painterly page. The name is lettered underneath in a thick amber brush script, with the occasion following in a quiet charcoal serif. It is built for a builder-mad child, and it carries just as well to a tools-and-trucks party, a digger theme, a joint party for two siblings, or any celebration where the invitation should feel handmade rather than printed off a template. The warm cream and amber palette keeps it cheerful without the primary-colour noise most children invitations reach for. Sending it as a digital construction birthday invitation brings the whole day with it: guests reply yes, no or maybe from their phones and you watch the responses arrive in real time, with plus-ones and meal choices tracked for you and reminders going out on their own. A shared photo album collects pictures from the party, and a matching thank-you note is ready once the last guest leaves. One practical note for a children party at this age: ask on the reply whether a grown-up is staying. At nine and ten the mix of drop-offs and stay-and-helps changes how much food you need and how many adults are on hand, and collecting it with the RSVP saves a dozen texts the night before.