My female Pekin duck abandoned her nest and after a few days we started cleaning out her nest and found three eggs that were trying to hatch. We had to help the ducklings out of their shell as the shell had hardened. So we have hand raised the three and they are like my babies. They are now 6 weeks old and I believe 2 are males and one is definitely female. Last night our grown male duck attacked the baby female and tried to mate her and she was screaming I ran outside and had to shove him off of her. I have the little ones in our fenced in front yard and the grown ones in the back where they free range but the little female had gotten out. Is this normal for a male to do, does he not realize she is still a baby? This has been very upsetting as he keeps trying to get in. What else should I do?