Heather Daybell, married to Chad's brother, Rexburg neighbor, and in-law to detective Hope, the detective who approached, and Chad was asked again for Lori's phone number and Chad stopped pretending he didn't know it. Heathers daughter is married to Hope's son.
She was never under Chad's spell and didn't particularly pretend to be impressed with him over their whole adulthoods. She was underwhelmed when Chad moved his family to the Rexburg area that she and her husband had lived in first. Plus, she called him out for going against Church teachings.
After Tammy's death began to be investigated as a murder, one the Tammy's kids believed HD to be the one who started rumors that Chad murdered Tammy, and believed her to be the main cause of Tammy getting exhumed and autopsied. However, there is no indication that HD would have any actual information that would be enough for LE to be so intrusive. She was suspicious with the timelines, such as the instant burial and whirlwind marriage to Lori, but she didn't have evidence, AFAIK.
However, Heather's being a closer relative to Detective Hope probably makes it easier for Chad's supporters in denial to believe she would have that ability. It's nonsense, of course, to think anyone can just get an inlaw relative who is a Detective to take on an investigation. But that is what the younger Daybells seemed to think a few years ago, and might think now.
MOO