I asked Ascensius and he said ok! To add a special touch, I bought a small race car candle holder with a tiny number 4 sticker on it. Fondant top was stamped with his name and a number 4 on top of the fondant star.
Unfortunately, I used the wrong setting on my oven and ended up baking each coloured layer for too long :(
The cupcakes turned out a little too hard, which was a shame. But overall they looked really bright and cheery!