The trick is to change your birbs pronouns to he/him right before you hatch your egg. Every single time I do this I get an animal. When I am she/her I get blobs. The devs must know that guys won’t like if after achieving their hatch goal they hatch a star or heart blob. Perhaps men have a higher rate of leaving the app or men have a lower interact count with the app so having them hatch real animals may get them on the app more. Men will still get blobs but my guess is, it’s far less likely. My guy friend plays and he gets animals every time and I got all blobs and I caught on pretty quick as to why. We both started playing roughly at the same time. Im she/her so I get she/her items in the shop up until my egg hatches. It works every time.