Can't find anything that says she's her sister-in-law (but did find some that says she's not), but this article says she took a lot of campaign money from Pelosi.
https://www.nrcc.org/2012/10/04/another-broken-promise-kathy-hochul-campaigns-with-pelosi/
Another broken promise - Kathy Hochul campaigns with Pelosi - NRCC
If one thing is clear in this election it’s that Kathy Hochul isn’t living up to her promises. In fact, Hochul is back at it – trying to mislead Western New Yorkers about who is bankrolling her campaign. What Hochul... Read More
https://www.nrcc.org/2012/10/04/another-broken-promise-kathy-hochul-campaigns-with-pelosi/
