"He's really having a tough time," his New York lawyer Benedict P. Morelli tells PEOPLE.
Since a six-vehicle crash in June – which left Morgan in critical condition and ended the life of his friend, comedian James "Jimmy Mack" McNair, 62 – the 30 Rock star, 45, has been "struggling," Morelli adds.
Though Morgan has been spotted using a walker, he relies on a wheelchair and it may be months before he can fully walk again.
Having suffered traumatic brain injuries, a broken leg and several fractures to his face, Morgan continues to undergo at-home therapy following his release from a rehabilitation facility in mid-July.
"He's making incremental progress," says Morelli. "But they'll have to wait another month before they assess him cognitively."
Reporting by MICHELLE TAN
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