Adding new chickens to flock

[girlyq]

Put 4 roosters and 7 pullets (3 months old Rhodies) in with 8 Comets (2years) after several weeks they tolerate each other for the most part.
But I want to add 10 Isas (20 wks) and six others (8 wks) to the flock Wil the roosters hurt the young ones?
Is this unwise?

 

[buckboy101]

If possible you need to put the new chickens with one or two of your current hens for a couple of days and then when you put them back in the coop, they shouldn't get picked on

 

[poultryluvr18]

One thing that I could add on to duckboy101 is I put my chicks in wire cages for a day inside the coop so they all kinda get used to each other a little more. I also leave the cages in for about a week so they can kind of hide if needed. They'll still get picked on, but hopefully not as much.