Sorry for hijacking your thread snow white, but I'm in a similar situation and not very sure what to do. We had three hens, one died a while back and the other one had to be euthanised on Friday. On Sunday, we bought two more hens, thinking the original (Babs) would be glad of the company. Babs is a Rhode Island Red, as was her companion. The new two are a Black Sex Link (Beulah) and a White Leghorn (Bridey), both smaller than Babs, in particular the Leghorn.
Babs is not at all pleased to see them. No idea what's going on in her head, of course, but she and the other hen were extremely close. Babs was very defensive of her and is fearless in the face of possible attack.
The Leghorn scarpers at the sight or sound of anything but the Black Sex Link is terrified of nothing but Babs, who started stabbing her back and head with her beak from the outset and won't leave her alone when they are together, so I've separated them to reduce contact.
Babs and the new pair are in separate compounds side by side. Babs gets to free range once she's laid her egg. When she's gone, I open the gate into her area to let the other two in to her side as it gets more shade. Babs wanders off but occasionally returns and marches round the hen compound, as if appalled at the invaders. She is effectively locked out of her own home, but given that it is too hot in the afternoon in the other area, I have no choice.
I propose to keep them like this for a couple of weeks and then introduce them to each other at night.
We have no need of more eggs, but might getting another Rhode Island Red as company for Babs be a good idea?
The good news is that despite the stress, Beulah laid an egg yesterday (first morning after her arrival) and looks to be laying another now. Mind you, yesterday's was tiny at just 29 g. Still, she's eating for Spain, so I guess the egg size will grow as she gets a bit bigger. The Leghorn won't come into lay for a few weeks apparently.