Alexander suffered respiratory problems
The 21-month-old, nicknamed Sasha, was treated for breathing difficulties.
He was released the following day.
Sasha got home today and is feeling much better after being hospitalised on Tuesday night with respiratory problems, a rep for Naomi tells Access Hollywood.
Fortunately, Liev, 41, had already planned to skip the LA premiere of his latest movie X-Men Origins: Wolverine to fly back home.
Its thought he arrived before Alexander became ill.
He and Naomi, 40, also have 4-month-old son Samuel.
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