Some Champions get bonuses or extra abilities when certain other particular Champions are "on the same team".  But how does that work, exactly?

For example, Atur and Kallia.  Atur says: "Immune to [Stun], [Freeze], and [Sleep] debuffs. [Only available when Kallia is on the same team]".  While Kallia says: "Attacks 1 enemy. Has a 30% chance of placing a [HP Burn] debuff for 2 turns. [Heals this Champion by 30% of the damage inflicted when Atur is on the same team]".  In fact, all three of Kallia's abilities get heal her "when Atur is on the same team".

What counts as being "on the same team"?  Do they both have to be conscious or do they merely have to start the fight together?  If they start together and then Atur gets knocked out, will Kallia still heal herself?  Is Atur still "on the same team"?

If they both have to be conscious to get their bonuses, let's assume Atur and Kallia start the same fight and Atur is hit with a Freeze effect, he'll shrug it off.  What if Kallia is unconscious, Atur is frozen, then Kallia gets revived while Atur is still frozen?

What if that Freeze effect kills Kallia such as from Rae?  Rae says: "Attacks all enemies. Removes all buffs. Has a 50% chance of placing a [Freeze] debuff for 1 turn."  If that attack kills Kallia, does Atur get frozen?

I'm tempted together a Tag Team squad with these two on it but I'd like to know precisely how it all works first.  Thanks!