In season 4 of the hit TV show "FRIENDS", Monica began an affair with her close friend Chandler. This happened at her older brother Ross's disastrous wedding to the English girl, Emily, in London. Monica was upset after a guest mistook her for Ross's mother and so she turned to Chandler for comfort (none of this is learned until season 5 though). They kept their relationship secret for a while but eventually their friend Joey found out. The rest of the group then found out one by one, until everybody knew. The two fell in love and eventually moved in together, forcing Monica's friend Rachel to move out. The two married and in the final episode their adopted twins, Erica and Jack, were born.

The two almost didn't get engaged because one of Monica's ex-boyfriends, Dr. Richard Burke, came back into her life. Richard was significantly older than Monica (21 years) but the two fell in love during season 2. They broke up at the end of that season because Richard was not interested in having children again. A chance meeting with Monica during season 6 rekindled Richard's passion, and he told her that he was willing to have kids if it meant he could be with her. When Richard discovered that Chandler was going to propose to Monica, he stepped aside so the two of them could be together. They had a romantic wedding aside from Joey's questionable attire, and discovering that Rachel was pregnant.