Who is the blonde girl that kisses Steve at his house?

When we see her in season 1 episode 8 "Time to Kill the Turtle," she kisses Steve, and then Chip says, "I've got 3 fucking kids at घर and you're balls deep in that? You're killing me." It seems apparent that Steve has been sleeping with her and Chip knows it.

In the season 2 finale, "Fiona Interrupted," she appears at the family रात का खाना and I think is supposed to be Chip's wife? या their sister? She's listed on आइ एम डी बी as Jamie Lishman (Lishman being Chip/Jimmy/Candace/Lloyd's last name.) Is this a different blonde girl? If it is, then who was the first blonde girl??

Can anyone shed light on this? Thanks!