Katherine Jackson has always been the rock of the Jackson clan, but a new report says that the ordeal surrounding son Michael Jackson's death may be taking its toll.

"Katherine has been crying a lot -- her eyes are really red, and any time anyone mentions Michael, she gets very upset," says Anne Marie Cruz, People magazine staff editor. "Right now Katherine's really struggling to hide her sorrow."

According to People magazine, on stands today, the shock of her son's death, combined with the family arguing over where to bury Michael and the funeral service that stopped traffic in all of Los Angeles has finally caught up with the Jackson matriarch.

But according to People, Katherine is trying to put on a brave face for Michael's three children, Prince, Paris and "Blanket," whom she currently has custody of.

"Katherine feels really terrible for the kids, but she's determined to stay strong for them right now," says Cruz.

Watch ET for more on Katherine and the Michael Jackson death investigation.