As of now, it hasnt been revealed how or why he travelled back in time, only him saying that he used the pocket watch she wanted to gift him and that it took him seven years to come back. The FL death isn't discussed yet and might have something to do with the king whom the ML killed the moment he regressed.

She became the ml's nanny immediately after her first child died and was obsessed with him to a tee. She was jealous of her own daughter getting attention and affection from the FL and was abusive to the young fl. The FL is a supposed beauty and after a certain kidnapping incident, angry thay the ML came back from the battlefield for the fl, she almost gouged out the eyes of the FL amd started gaslighting her to make her think she is ugly. Poor FL to this day is unaware of how disgusting her prents truly are, happens to love them very much and believes her mother's words to be true and is extremely insecure. She is honestly better off without them and shouldve decided to cut ties with her father when he sold her off to an old, foreign noble for money to who*e around. But, no. Instead she asks him why and he has says the same thing every shameless ab*ser says - that nothing has happened yet, and she could've gone to the ML for help. Ugh! Like seriously? And they pretend like nothing is wrong at the wedding where he walks her in? Like seriously babe?