PORTLAND, Ore. (KOIN) — One month after the fatal crash that killed Jennifer and Sarah Hart and four of their six adopted children, search efforts continue for the couple’s two missing children.

Mendocino County Sheriff’s Office spokesperson Capt. Gregory Van Patten said deputies are conducting shoreline searches each day for Devonte and Hannah Hart, so long as daily calls for service allow for those efforts to take place.

Devonte, 15, and Hannah, 16, have been missing since the family’s car was found crashed off the Mendocino coast in California on March 26. They are presumed to be dead.

The crash is being investigated as a crime, and Mendocino Sheriff Thomas Allman has released toxicology results showing that mother Jennifer Hart, who was driving the vehicle at the time of the crash, had a blood alcohol level above the legal limit.

Toxicology results also show that Sarah Hart and two of the three children whose bodies were found by the site of the crash had ingested significant amounts of a drug found in Benadryl, known to cause sleepiness.

Van Patten said Thursday that toxicology results for the third child discovered by the crashed vehicle and Ciera Hart, whose body was found nearly two weeks after the crash, are still pending. There was no explanation as to why the report for the third child was taking so much longer to complete than the reports done on Sarah and the other two children who were found at the same time. Investigators have not released the names of the children whose toxicology results showed signs of the drug.

The sheriff’s office has not released any additional details regarding how much of the drug was found in the three family members’ systems.

Van Patten also confirmed that deputies have not discovered any animals or animal remains near the crash site. According to Woodland neighbor Dana DeKalb, the family had two dogs; those dogs were not found left behind at the family’s home.

Since the Harts’ car was discovered, records have been located showing a string of child-abuse allegations, starting in Minnesota in 2008. Sarah Hart was convicted of misdemeanor domestic assault against a child in that state in 2011. Oregon Department of Human Services investigated abuse and neglect allegations against the family in 2013. Three days before the family’s fatal crash, DeKalb, their neighbor, contacted Washington Child Protective Services with concerns that the children were being abused and starved.