Cubs will stay with their mother for up to two years until she kicks them out. After that, the juveniles will often stay together for a bit. Adult Toms don't tolerate other Toms, females, or juveniles, unless the female is in heat. @bearpaw Maybe Dale will chime in.
Yep, momma with grown cubs. I tracked a trio in fresh snow where all three had the same size adult tracks. After tracking them for 300 yards, I finally noticed that one of them walked a fairly straight route, and the other two consistently swerved back and forth across the straight one's tracks, veering to a stump on one side, back across to check a log, etc. It was a momma and two still curious grown cubs, all with tracks the same size.
Also, it appears that two of the cats in the pic have juvenile bars and spots on the inside of their legs.