A couple of episodes gave hints that Voight might be Erin's father. Was this storyline ever explored? Was the identity of Erin's father ever revealed?

Bunny making a scene as usual, screamed Voight would like to forfet that night.

Voight knew Bunny long before Erin, she hung out at cop hang outs. (Told Erin in the car while on a stakeout)

Voight bailed Bunny out of her debt. He bought it. Told her repayment, stay away from Erin. She sid ok you're better parent.

The Jimmy whoever guy that got out of prision that Bunny sent pictures over the years, DNA proved he was not father, thanks to Halstead.

When Lindsey left for NY, her last storyline, Voigjt covered up Bunny killed her beating husband. He always cleans up bunnys messes.