What I don’t get is....?

I don't know this is true or not , it is said that Dylan (mc) is illegitimate child and Emily Emily is pure blood .
May be this is the reason he wanted to propose Emily.

Really it seems she was really sad that the mother died... maybe she didn’t know.....
Is that why her hair color is the only one different?!
But doesn’t he want to marry her family for her family support does it matter if she was illegitimate child or not she still carry her dad bloodline, and is considered an accepted daughter so it didn’t matter if she was the daughter of his main wife or another women right? He just needed her family support.

The person who ripped the chapters from another site forgot to upload chapter 1, the chapter 1 right now is just the prolouge.
So basically, the grandfather fell in love with the mother as she was a beauty, but was unable to pursue her because she was already engaged
He still kept in touch with the family and they promised to marry their firstborns. The grandfather is sure that the Duke must marry "Hailey", a child who resembled their mother's beauty, however Hailey is actually a son. And Emily has the closest resemblance after him, and is also a woman.

I see that makes so much more sense thank you, I had a feeling it was because of the grandfather. She isn’t an illegitimate daughter right?

Oooooh, thankss

People have already explained it to you, but in case you're also interested in reading the chapter then you can check out m-an-ga-dex (erase the -). I can't drop the link or even type out the full name of the website because mangago deletes it automatically lol. But if you google it and search the title of the webtoon, you'll find the first chapter (translated).

Thank you so much

Thank you sweetheart