Wiz Khalifa -- Gotcha Amber! I Just Threw a Birthday Bash for Sebastian

Wiz Khalifa believes in the motto, "If you don't succeed ..." because he threw a belated birthday party for Sebastian and this time the kid showed.

Wiz threw the bash at his home in Silver Lake Thursday. It was almost a carbon copy of the party he tried hosting last weekend, when Amber and 2-year-old Sebastian were no-shows.

Amber was not present this time around, which apparently was just fine with Wiz. He used his custody time to bring friends and family together to celebrate the BD.

Here's the good news ... Amber's name wasn't even mentioned, which is at least one small step in lowering the volume in what has become a super-bitter custody war.

The party was pirate-themed, so it's too bad Amber didn't show. Imagine her walking the plank.