Examples of these gifts include:
A Tshirt with a cartoony fish pattern for his birthday. (Where did Sirius get it?? Stores don’t sell these in adult sizes?? And it hasn’t been made larger with magic because the fish are the same size as they are on the kids shirts.)
One of those fish shaped hats that are supposed to look like the fish is eating your head.
(Feel free to add more if you want to)