The Biebs and his mom, Pattie Mallette, are vacationing together, which is a big deal. They've been estranged for years, and only recently started reuniting. Based on Pattie's own words ... it's going very well.

She posted this pic and gushed ... "I'm so proud of the amazing young man you are, and the young man you are becoming. None of us are perfect and never will be, (so we will always need patience and grace for each other), but your genuine growing relationship with Jesus is evident in the choices you are making daily and the good 'fruit' you bear. I admire your character and integrity."

Since canceling his Purpose Tour, in part to focus on his religion, Justin's reconciled with Selena Gomez ... and now his mom.

There's a definite pattern.