The Big Bang Theory's Penny (Kaley Cuoco) and Leonard's (Johnny Galecki) story already spoiled what happens next to Georgie (Montana Jordan) and Mandy (Emily Osment) on Young Sheldon. After going through a rough patch due to their unexpected pregnancy news, things seem to be finally falling into order as Mandy and Georgie learn to at least be civil with each other despite still being broken up. While it's still difficult to predict what exactly happens to them in the long run, the ever-popular The Big Bang Theory has already given an idea of how their reconciliation will pan out in the near future.
Young Sheldon season 6 episode 3, "Passion's Harvest and a Sheldocracy" sets up Mandy and Georgie's arc to be similar to what happened with Penny and Leonard's story on The Big Bang Theory. After refusing her ex-boyfriend's help multiple times, Mandy finally reached back because she was kicked out of her apartment. Georgie couldn't be more gracious and helpful. Despite his own predicament, he welcomed her to his own home — which is really the Cooper family garage. Georgie has also been considerate and kind as he tries to keep Mandy as comfortable as possible. This is reminiscent of Leonard's treatment of Penny, which led to them being together on The Big Bang Theory. Despite Sheldon's (Jim Parsons) involvement in their relationship, Penny stuck around and ultimately married Leonard. Essentially, if Georgie continues to be great with Mandy, he can win her over, the same way Leonard did with Penny.
Despite their new living arrangements, Georgie and Mandy are still broken up in Young Sheldon season 6. The only reason why they are still in contact is because they are pregnant. Things might change, however, now that the former couple will be bunking in the Coopers' garage. Between that and Georgie's perseverance, the chances of them rekindling their romance are now higher than ever. In any case, she only split up with him after she learned that he lied about his age. Had it not been for that, it's likely they would still be together. This makes it easier for them to pick things up again in Young Sheldon season 6, especially now that they are going to spend more time with each other.
Aside from Georgie, Mandy moving in with him also makes her more accessible to the Coopers than ever. This allows the family to get to know her better. Mandy already has a great relationship with Meemaw who has dealt with something like this before when George (Lance Barber) and Mary (Zoe Perry) also got unexpectedly pregnant. On the flip side, Mandy will also be involved in many of the family's shenanigans moving forward in Young Sheldon season 6. That being said, if things don't work out for Mandy and Georgie, this would make their permanent break up more heartbreaking as she would also have to cut ties with the rest of the Coopers.
For context, there was never a mention of Mandy or their kid when Georgie appeared on The Big Bang Theory. It was established that he had a few ex-wives, but they were never named; meanwhile, there wasn't any indication that he had a kid. Given this, it's difficult to predict what exactly will happen between them. If anything, this makes their narrative very interesting because Young Sheldon has creative wiggle room to craft it.