The L.A. County Sheriff’s Department wants to interview the Oksana Grigorieva‘s 12-year-old son, Alexander Dalton, also known as Sasha, according to TMZ.com. They believe the boy is a witness to many of the blowups between Mel Gibson and his mother. Alexander, whose father is actor Timothy Dalton, lived with Mel and Oksana while they were together, and is considered “a very important witness” to Sheriff’s investigators. It’s believed Alexander didn’t see Mel’s attack on Oksana, but was in the house when it occurred and heard what was going on and saw his mother’s injuries. He’ll also be called on to testify in the custody battle for his half-sister, Lucia. Meanwhile, Oksana received several anonymous phone calls this week from callers who are angry about her accusations against Mel. One of the calls was interpreted as a death threat. The LAPD is investigating.