Milwaukee is set to resume its season following the All-Star break, the first time the club will assemble since Hader's years-old racist and homophobic tweets surfaced during the All-Star Game.
"He's going to have to work very hard to re-earn the trust of some people who may question who he is right now," Stearns said. "I think I know who Josh Hader is, and I personally do not believe that these comments represent who he is as a person."
The 24-year-old Hader apologized and took responsibility for the tweets after the game, saying they did not reflect his values or the person he is now.
He'll return to a conflicted clubhouse, though teammates seem eager to accept Hader's apologies.
"It's a lot to deal with. I can't really defend anything he said. I know it was a long time ago but at the same time, those tweets are wrong. It's a lot," third baseman Travis Shaw said before an optional workout Thursday at Miller Park. The team's five All-Stars, including Hader, did not take part.
"I can defend the person he is now. I would have never guessed that something like that would come from him," Shaw added. "He's a good kid now. I'd never in a hundred years guess that he'd say something like that."
Hader may address the team collectively. At the least, he'll have questions to answer.
"We want to be there and support him, we want to hear what he has to say," veteran Ryan Braun said. "And ultimately as a team, you want to be able to move on from it."
Until Tuesday, Hader was best known as the hard-throwing left-hander in the Brewers' strong bullpen. He has been a lights-out reliever since coming up to the majors in June 2017.
Hader's 6-foot-3 frame, long hair and glasses give him a unique look on the mound. Hitters often flail at his fastball and buckle when he throws a slider. The filthy stuff has allowed Hader to strike out 89 in just 48 innings this season.
Several of Hader's tweets from 2011 and 2012 came to light Tuesday while he was pitching in the All-Star Game. Hader learned of the situation when he left the game. He said he did not "vividly" remember the tweets.
"Being 17 years old, you make stupid decisions and mistakes," Hader said Tuesday night. "I was in high school. We're still learning who we are in high school. You live and you learn. This mistake won't happen again."
MLB announced Wednesday the commissioner's office would require Hader to participate in diversity and inclusion initiatives in addition to sensitivity training. Hader will also meet with Billy Bean, MLB's first ambassador for inclusion, on Friday.
"We have to be 100 percent transparent," Bean told USA Today Sports. "I'll learn a lot more about him when I speak to him. He will have every opportunity to do right by the league and be a role model if he wants to. He could grasp this opportunity from a very unfortunate experience and be a role model."
Stearns said the Brewers followed the league's lead in not disciplining Hader.
"Josh is going to be here [Friday]. He's a part of this team. We care about him as a teammate and we can do that at the same time as being offended and really disappointed in the comments that came out the other day," Stearns said.
A similar sentiment was echoed by nearly everyone else in the clubhouse Thursday. Team chemistry that has been a strength of the club that won 55 games before the break will be tested.
"I love the kid, I love him. A lot of those tweets were song lyrics that I recognized," outfielder Keon Broxton said. "I know it's just him being a young kid. Not saying it was right, but I do forgive him and can definitely look past it."
The Associated Press contributed to this report.