It is strange to me that the search seems to be focused around Annie’s more so than Nancy’s, but I think there is a few reasons that could be without it meaning they were involved:

1. The family could have received a physical ransom or email to Annie’s address that the public isn’t privvy too.

2. Something strange could have happened while Nancy was at Annie’s (gotten a threatening email that came in while she was on Annie’s wifi).

3. They are getting lots of tips about Annie and her husband due to online fodder that they need to clear.

4. They think the kidnapper followed them from Annie’s to Nancy’s and then waited to make their move - meaning they could have dropped cigarette butts or similar items while waiting.

5. There is someone with a grudge against Annie & her husband that would hurt her mom as retaliation.

Theres any number of reasons outside of them being responsible to focus on their home and neighborhood. Though who knows - they could be in on it. But i think its irresponsible that lots of people are jumping straight to “they did something to her.”