I bought some rouen ducklings for my lame broody to care for. She was sitting on eggs and I replaced them. They are probably 3 or 4 days old - came in mail. She is sitting where the eggs were and when the new ducklings comes close she pushes them away. I only put them with her about 15 minutes ago. She doesn't seem mean, just pushes them. How long before I will know if she will adopt them?