Bobbi Kristina -- Grandma FOLDS In War Over $20 Mil Inheritance

Bobbi Kristina's grandmother Cissy Houston has BACKED OFF her attempt to keep Whitney Houston's money from Bobbi Kristina for years -- we found out Cissy has settled her beef with BK.

TMZ broke the story ... Cissy and Pat Houston (co-executors of Whitney's estate) ... had filed legal papers hoping to drastically change the way Whitney's fortune would be paid out to 19-year-old Bobbi .. because they felt it was "too much, too soon."

As it stood, BK was to receive her money -- an estimated $20 million -- in 3 separate chunks ... 10% when she turns 21 ($2 mil), just under 20% at age 25 ($4 mil) and the remainder when she turns 30 ($16 mil).

Now, we've learned ... the case has been dismissed after Bobbi and Cissy reached an agreement ... and sources tell us Whitney's original plan for the payout was virtually unchanged.