New additions to the flock

[Lifetime chicken lover]

Hi!
After a tragic loss of 7/10 chickens, and some major construction to fortify the coop, I decided to get 4 new chickens to add to the flock.
The new chickens are very skittish and nervous. They are also displaying some aggression towards my other 3 chickens. I know that they have to establish a pecking order, but these new girls are really mean! I feel like I made a big mistake getting more chickens.
How do I make the transition easier for everyone? Do I just have to leave them be to establish their pecking order? My 3 girls are so scared of the new chickens and run to me for protection whenever I'm around.
Anyone have any advice?

 

[Lifetime chicken lover]

and no, against all advice, I did not quarantine the new ones.

 

[Scrummycat]

Not sure if this would work in your situation, but I keep my new hens in a separate area of my barn for a few weeks, then I will let them ALL out to free range together in the evenings so they meet outside and if things get too intense they have room to run away from each other. Once they are all eating scratch together fairly peaceably (after 1-2 weeks of spending 2 or so hours together each evening), then I will put a wire dog crate inside their run, with the new hens inside, so they are together, but not really "together", if you know what I mean. Then they go back to their quarantine pen at night. I do this for several days, until everyone is used to sharing the same space, then at night when they are all asleep, I sneak the new hens in and put them on the roost. In the morning, there might be a little squabbling, but not bad. I try not to interfere unless there are feathers getting ripped out and/or blood. When I've done it, I was adding two new hens to a flock of seven, so the established hens outnumbered the new hens quite a bit.