They didn't know the sex of the baby at the time and were planning a yellow and green nursery, although she said she didn't care if the quilt matched the nursery.
Up until this point I hadn't seen any fabric with sharks, but I did an internet search and found lots of fabric with sharks on it. Including the one that I ended up using.
Plus the added bonus: text. As a graphic designer, I've always loved text, so once I saw this fabric, I knew that was what I was going to use.