Family Mourns Tiger -- Shrine Erected

It's been three days since a 2-year-old Maltese named Tiger was killed by Samantha Ronson's bulldog Cadillac -- and now TMZ has learned Tiger's owner has set up a makeshift memorial to honor her fallen pooch.

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This shrine has been set up in the owner's apartment -- in the same West Hollywood building where Tiger got into that fateful confrontation with Cadillac early Monday morning.

As for Tiger's alleged killer -- we're told Cadillac is still on the East Coast.