i would *not* take any bone out unless you find something to replace the calcium from that. they are kittens who, greater than adults, need calcium for their growing and developing bones.
i wouldnt worry about it really. not unless you see chunks of bone coming out in their poo... of which im not sure is possible or if it was would be indicative of a worse problem.
Chris- Husband, 04/30/77
Cailyn- Daughter, 07/05/99
Jeffrey- Son, 03/24/06
Alex- Son, 03/25/09
Mister- Black LabX, M, 08/06(?)
The Shadow Stalker- Gray Tux DSH, M, 04/04
The Mighty Hunter- Black Tux DSH, M, 04/04
Baby Girl- Tabby DMH, F, 12/03(?)
Frances- Tortie, DSH, F, 2007(?)