No, I don't think so. If ever she would have an affair, it would have been with the 1st.
At first I thought the kid might be the crown prince's. But they broke up a long time ago and the crown Prince isn't the type of person to keep up that relationship.
Concubine Tian’s brother was committing sexual crimes & murders to woman & children. He almost got caught. So she make a deal with 2nd prince to save her brother from being punished, and hide his crime.
And then, as part of the deal, she have to help him get the guards away during the night that he, his brother and his mom planned to kill OG ChaoYi.
This is the plan and what happened that night:
1. Tian (consort) get the guards away from the lake area using her dog as excuse.
2. 8th prince invite ChaoYi to the pavilion on the lake.
3. The teacup already laced with paralysis/sleeping drug lots by 2nd prince.
4. After drinking tea and talk near the lake, 8th prince pushed ChaoYi into the lake.
5. Torment by guilt, 8th prince jumped in it to kill himself too.
6. ChaoYi is strong guy, he quickly swim and save 8th prince to shore.
7. 8th prince saw that both of them survive the lake, and went unconscious.
8. The mom came and pushed ChaoYi back into the lake, and ChaoYi died then.
9. 2nd prince with his subordinates came to take 8th prince back and clear up the area to make the death looks like accident.
10. MC transmigrated into ChaoYi’s body and swim back up. Met System.
…………
The reason why 2nd prince killed ChaoYi is because ChaoYi found out about the crimes his whole family did. I think he found out when he tried to clear the Crown Prince’s name. Because 2nd prince is the bad guy who planned the Crown Prince to lose his title and 1 year house arrest.
So, to save his whole wretched family, 8th prince being gaslighted/manipulated into helping to kill his own best friend.
What if he and the consort was drugged by 2nd prince and ended up doing the deed?
And they got caught by emperor, but emperor a nice dad, so he just take the Crown Prince title and confine him for 1 year. And keep the whole accident a secret?
What is the 2nd Prince 's connection to the consort? Is the newborn Prince a product of their affairs!? Those two are really suspicious.