It was temporary, It's because the cold poison in her body. The person who was poisoned with cold poison cannot get pregnant... Later on when she got rid of the cold poison, she should be able to get pregnant normally. In fact, Jing wang told her this to have her break up with OS. (He seemed to forgot that if she cannot got pregnant, she cannot marry him too.Yes we have.....Once when travelling, MX and OS met old Jing Wangfei who proceed to bash MX for being the abandoned fiancee of her son and bla bla bla. The mother in law appeared and defended MX. There was also one of Jing Wang's "clever" plan to ruin MX&OS's marriage, turned out the plan was to Invited Qin YuYan's sister who was in love with OS to crashed the wedding..... OS's reaction there was priceless, it made everyone speechless . "Wait......." "Shao Chen ge ge, how could you marry someone else?" (the guests were looking at MX with eyes full of symphaty)
OS looked down coldly at the woman, "who are you?"
the guests, "........"
" Shao Chen ge ge, don't you remember me? I'm Yu Jiao." The girl explained with teary eyes.
"Yu Jiao?" OS frowning, he completely cannot remember who this girl was.
One of OS's bodyguard came near him and gave a reminder with a very low voice, "Shizi, she is Mo Bei princess, Yu Jiao...."
MX looked at OS, wanted to see his reaction, saw OS cold eyes and he said, "Do not remember!" Anyway, the next day, QYY's sis came to XiaoYao fu to meet with Xiao Yao wang & wangfei. MX and OS was also there bc they have to give a greeting to parents (the tradition after marriage). When the servant notified them...
MIL: Who's she? I don't know her! (Even though QYY's sister introduced her self loudly and made a scene, so everyone there should know who she was)
MIL (while smiling): Wangye, do you know her?
FIL (thinking for a while, while staring at MIL):...... no, I don't
MIL: then we shouldn't let her wait, tell her, she got the wrong residence.
And also how they were glad OS got married bc then they could travel together without worry (leaving the residence management to MX). Edited: They got married in chapter 777 to 779 (I had to check the raw first).
Yes, Jing Wang tried to summon and use them using the jade token, but unfortunate of him (or should I say he's very stupid, honestly all of his plan and MX's other enemies were very stupid and shallow) the target was visiting MX in her manor (OS was also present). So they caught him soon after.I forgot what happened, but I think they took it, but MX remembered the map, so she and OS went treasure hunting together. They met Jing Wang, Qin YuYan, plus some bodyguards on a way. In the end OS&MX got the treasure. Initially OS planned to let MX have all the treasure. But before anything was said, MX offered 50% of the treasure, then bc OS looked in silence, she thought that he disagreed so she offered him 70%. In the end, I forgot OS got 50% or 70%....Yes, the one who poisoned her was old Jing Wang. He did it so MX's parents would agree of the marriage between MX and Jing Wang, since it would be hard to find a marriage partner now that she had cold poison (since she cannot be pregnant) and even more to be first wife, not concubine.
Which prince OS or Jing Wang? R you asking about Jing Wang's motive for forcing MC to marry him? ML was the one that saved the past MC when she was kidnapped and forced to eat the cold poison when she was little. He was trying to fight with the kidnapper and got injured, so he left her in a visible spot. That's when little Jing Wang saw/found her, and then when everyone came, they assumed that Jing Wang was the one saving her and both Jing Wang and old Jing Wang shamelessly took the credit. ML at first saw MC as fragile little sister that needed to be protected, that's why he gave her helps when he met MC at the beginning.
To answer your second question, it talks about it in chapter one-- he wants to marry Murong Xue (main character) as a concubine because he wanted to marry Princess Yuyan as his first wife whereas the heroine was originally suppose to be the first wife but he wanted to demote her but still be married to her (political reasoning) to which she declines.
I don't know how to write his name but The male lead meets her when she goes to her fathers grave (at least from what I can remember) and saves her from Ye Yichen (ex fiance). He helps and annoys her multiple times and later on and gives her a bracelet (that has their names engraved in it) where only the princess who will to marry into his family can wear and it literally can't be taken off her wrist (unless she chops off her hand) while promising her that he'll marry her no matter what.
It's ok One of the motive was there's a piece of treasure map in Murong Xue's dowry... It contained a very vast amount of treasure which Jing Wang later failed to gain.
While old Jing Wang's superficial motive was bc Murong Xue looks very similar to her dead mother. That's why later when introduced, old Jing Wang Fei was very against Murong Xue marrying her son.
But the main reason is, Murong Xue's father was a strong and talented general. Before his death, he had trained hundreds of dark bodyguard (or assassin? or perhaps ninja? the translator translated it as dark wei). Anyway they're very powerful, possibly as strong as Ouyang ShaoChen's dark bodyguard. After MX's father's death, they went into hiding, waiting for the right successor to appear. The successor must be of Murong's blood and had an special emblem made of jade to be their leader. Old Jing Wang speculated that MX's father meant all along to pass the leadership of the dark bodyguards to MX instead of her brother.