public void ChildUpdatedItsState(Waterling pChild, WaterlingState pState)
 {
     if (Underlings.All(u => u.State == WaterlingState.WalkedIntoAWall))
     {
         State = WaterlingState.FillAndClimb;
     }
 }
            public void SpawnUnderling(Point pAt, WaterlingState pJob)
            {
                var underling = new Waterling()
                {
                    Position = pAt,
                    State    = pJob,
                    Parent   = this
                };

                Underlings.Add(underling);
                waterlings.Add(underling);
            }