OK OK but BartTimBer??? I fell into a rabbit hole on AO3 and they are honestly the sweetest, but alot of the fics I've read so far are based in AUs or Bernard Tim and Bart already know each other so here's my take on how they end up dating:))
OK, so, what happens:
1. Tim and Bernard are already dating.
2. Bernard is sort-of aware of Tim being Robin. He knows, but hasnt been explicitly told, if that makes sense. Mainly so Tim can say he hasnt told his bf that hes Robin so Bruce doesnt make Jonn erase Bernards memories witbout fear of lying. Its a he knows he knows situation, if that makes sense
(I love the idea that Bernard started his conspiracy theory blog in high-school for 2 reasons: Fun, and to Annoy Tim into Admitting the Truth because the idea that he and Tim both figured out who Robin is through observation is funny to me), and eventually Tim admits it when delirious whilst Bernard is doing first aid on him because yes pls EMP Bernard
Sorry, back on track;
3. Bart meets Bernard through Bernard's conspiracy videos dicord server.
(Bart likes conspiracy theories, he thinks they're fun, and after all the BS Young Justice has seen and gone through he's gor loads of random material which would make a great conspiracy video; just absurd enough to be interesting. In consequence, Bart and Bernard chat alot, bouncing ideas off each other and becoming fast friends)
4. Tim and Bernard talk abt and consider polyamory and how that would work, boundaries and consent etc etc, and Tim starts taking an interest in dating Bart.
4. Tim and Bart start dating, Tim is also dating Bernard and although both are aware of each other they haven't necessarily met (mainly due to differing schedules, and coincidence)
5. 1 day Bart and Bernard end up meeting I'm person, (through Tim) and realise they are each others Discord friend :))
6. After a while, Bernard and Bart start dating, whilst Tim dates each of them as well
Gradually Tim, Bernard and Bart becomes a throuple
And they live together and get cats they've rescued from the streets :))
Side note: At some point during all of this, Bernard becomes an informant like Oracle for Young Justice, lightening Oracle's load and getting into the hero game to the point that Bruce allows him to be in the know, although at this point he's known for ages lol