'Making a Murderer' Brendan Dassey's Family: How About Tat?

Brendan Dassey's family has a lot to celebrate ... but their timing is off, because his mom got a tattoo decrying his imprisonment 20 minutes before a judge ordered his release.

Brendan's mom, Barb, and a family friend got matching tattoos -- "Justice for Brendan" emblazoned on their thighs, minutes before the appeals court decision.

Funny enough ... Barb thinks the tattoo ended up a good luck charm of sorts and contributed to Brendan's sudden good fortune.

The kicker ... when Brendan gets out he says he'll get a matching tattoo.