Adding pair of call ducks to a single hen?

[Onemoreduck]

I just got a pair of young calls to add in with my hen after she lost her drake earlier this year. The older hen is chasing the young girl, biting her, and grabbing her feathers. I know a pecking order has to be established, but how much aggression is too much? I don’t want the young girl getting hurt! She’s being chased in and out of the water!
TIA!

 

[Miss Lydia]

This is why you introduce with fencing in between so they all get used to each other. A dog crate works for overnight in a coop this way they can be together but the little female can't be picked on and stressed.
https://www.backyardchickens.com/ar...using-the-“see-but-don’t-touch”-method.67839/