Smith has missed the majority of the current campaign due to his voluntary involvement in an alcohol treatment centre, but the linebacker was restored to the active roster last week and could make his return against the Carolina Panthers on Sunday.
Whitner believes that the time off was good for his teammate and that he is now ready to focus on his football commitments without other distractions.
"He looks happy and healthy. The key is to move forward and not dwell on the past and [I] think he's ready to do that," Whitner told reporters.
Smith has also expressed his belief that his short break from the team helped him overcome his problems.