This was a gift from Loupy. The description is also by Loupy based on the Bluey episode "Bike Race".

So, after the cubs played Royalty with Bluey, with Loupy as princess and Snow and Fiona has lady in wettings (as Bluey called them, misreading, lady in waiting), the day was still young and so Bluey wanted to play more. When she saw the colored bike of the padded trio, she had an idea. Soon enough, the three cubs were racing in their toddler bikes, special oversized ones from cuties inc. originally planned just for shoots for commercials but that were too cute to be thrown away. The fact it shows the nappies of the three youngsters sure made Bluey giggle as they all raced toward the end.

Art by Felix Cooper – https://twitter.com/CooperPickless
Loupy belongs to Loupy - https://www.furaffinity.net/user/loupylupine
Fiona belongs to Feefers - http://www.furaffinity.net/user/runt