Lewis and Childress were seen at Jeff Ruby's in downtown Cincinnati, and Lewis even took the time to introduce Childress to patrons, according to WCPO-TV.
The Vikings fired Childress in November after a disappointing 3-7 start. Childress' name has been linked to a series of assistant coaching vacancies, but Lewis has not promised wholesale changes on offense, despite a disappointing 4-12 season.
"They're clamoring for heads and I understand that," Lewis said of the fans on the team's site Thursday. "I'm not ready to give them heads and we'll see what happens. I understand the frustration. Minimal (staff changes) might make things better, more productive. How do you get up and going? You have to be prepared ... a new system, a new nomenclature is harder. If we lopped off some heads, maybe we'd get better. But maybe we wouldn't.
"We're not very far off where we need be, but we need to be more demanding in certain situations and we need to be better."
"We've been all over the board a little bit too much and I think we have to focus in on what we are and what we're going to be and how we're going to do it," Lewis said. "The most effective offensive teams in the league do things over and over again and they build upon that. More with less.
"What upsets me is I can't tell who we are. My disappointment is I can't tell you what we are. The key to offense is to be offensive and stay offensive. What we are is a big statement. It has to be all-encompassing."
The Associated Press contributed to this report.