Parenting lights to monsters

[mysteryman141]

Hey, is there a way to parent a spotlight and a billboard to a prop_movelinear entity, specifically the 01_01_leviathan_tunnels.ent. I've tried 

Code: (Select All)

bool Entity_AttachToEntity(const tString &in asName,const tString &in asParentName,const tString &in asParentBodyName,bool abUseRotation,bool abSnapToParent=false,bool abLocked=false)

Entity_AttachToEntity("Billboard_monster","01_01_leviathan_tunnels_1","01_01_leviathan_tunnels_1_Body_1",true,false,true);

 but I get an error that reads "Could not find any entities with name 'Billboard_monster' for Entity_AttachToEntity.
Thanks.