Drug-plagued son of Diff’rent Strokes star DANA PLATO killed himself right before Mother’s Day.

Tyler Lambert, 25, who battled drug addiction and depression since his mother’s suicide 11 years ago, was "always miserable around this time of the year," a family friend told The ENQUIRER.

With memories of his mom’s intentional drug overdose on May 8, 1999, a still grieving Tyler committed suicide two days to  the anniversary of her death, leaving a morbid suicide note, The ENQUIRER has learned.

Prior to his death, Tyler went on a drug binge ending with the barrel of a shotgun in his mouth and pulling the trigger, The ENQUIRER has confirmed.

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