Jim Lewis told The Associated Press on Thursday that Cruz began living with the family after his mother died in November. He said Cruz was quiet and very respectful but also sad.
"They took this kid in. They had no predilection that anything like this was going to happen. He was a very mild-mannered kid. He's going through some tough times with losing his mom, but he obeyed all the house rules. He lived here without any concerns or issues for almost three months and they are shocked and horrified by the allegations that are being made," Lewis told NBC 6.
Lewis says Cruz had an AR-15 rifle in the home with them but it was kept in a locked cabinet.
"We have no- No way to explain motive. No way to explain why he went to this school. He never talked about anything, about having any hard feelings about anything at the school. The young man has been described as a little awkward, little quirky, but nothing to explain this."
Lewis says the family -- who he declined to identify -- has been cooperating with law enforcement, who have been searching their home. He also said the family's own son, a junior at Marjory Stoneman Douglas High School, was at the school when the shooting happened and is shaken up by it.
Cruz has been charged with 17 counts of premeditated murder in the Wednesday afternoon shooting in Parkland.