Here are the facts:
Fact 1. Same short style hair.
Fact 2. Same bug eyes...(eye shape)
Fact 3. Same pointy nose, (don't sue me Labeouf/Gahan)
Fact 4. Same face shape... uhh
Thats it! I figured it out. Shia Labeouf is Dave's son! He must have done it with a chick while touring with Depeche Mode, then forgot about her and she never made a big deal about it because she knew the kid would be talented. So she just keeps her mouth shut while Labeouf brings in the greenbacks. Nah that's probably not true. Oh well what you all think?