Is that group all females too? I wouldn't really worry if I'm being honest. I've only seen birds get hurt from mating when it goes wrong. Never just from the difference in size
Sounds like the older girls haven't accepted him yet. Logically, he wants to provide for the girls that have accepted him, hence driving away the older girls. He'd still like to be able to have them in his group, so he's making attempts to mate with them. They're refusing. Probably because he's...