i did a lot of hatching this Spring, and ended up with 11 roosters out of 17 silkies.  As they matured, one by one i had to pull roosters out.  This started at about 5 months.  It would look like they were getting along, and then my large showgirl roo would decide to violently attack one of the other roosters.  i'm sure if i had not been there, they would have been killed.  i had roos pulled out into hutches, crates, all kinds of things, until i could rehome them.
i just have the one showgirl roo now, in a pen with one hen (his other two wives are off raising babies).  i would never attempt to keep him with another rooster, no matter how many hens.  i've heard of folks being able to keep a couple roosters in the same pen.  But not sure i would try it after what i've experienced.
BBK, sorry about Mr. T, and sonew123, really sorry for your loss.  Those silkies may look cute and fluffy but the roos can be very ferocious.