(Yes a smudge stick is same as sage... one "smudges" with sage )

You may still have things in the house that the evil has anchored to... even a piece of jewelry could do it...books, "games", other items/icons...

It could be something environmental as in a small gas leak (since it's affecting the whole family) or carbon monoxide... have you had monitors placed in the house?

Has the family changed foods being eaten, medicines or supplements, or the type of pesticides being used?

Breathe... you can figure this out...

Greater is He that is in you than anything in the world.