Thank you for choosing this website. Congratulations on falling in love with someone from you would like to spend the rest of your life with. Sounds like you have been accepted by his family as well with the exception of his eldest daughter. Your question is how to make that transition smooth and also what is your best chances of him proposing to you.
Let's address the first issue. It would be very important to gather as much information as you can about his older daughter in terms of her likes, dislikes and attitudes. Since I have no idea how old she is more specific suggestions will have to wait. Younger daughters will still depend looked to their father for support and attention. They may view you as a new rival making it difficult for you to be accepted. Older daughters who have a life of their own may simply be interested in their father's welfare and although there is a possibility that they may have some preconceptions they will be easier to get along with since their tastes are more mature.
I would strongly recommend spending as much time as you can talking with your boyfriend about this daughter. Most men are proud of their daughters and see them as a reflection of themselves. This will prepare you to be able to speak in a positive way towards her.
Should things not go well you can always rely on your relationship with your boyfriend and make it clear to his daughter that their relationship is extremely important to you and should be preserved. By deferring to their father you may be able to resolve most of the difficulties of being a step parent.
As to your second question of whether or not he will finally proposed you that depends on your ability to keep the relationship active positive as you build the trust that is necessary to proceed to a marriage. Is often important to ask delicately previous relationship the men had. Information about how they met and how they decided to eventually split up is always very helpful in determining that man's expectations in your current relationship.
I see that you are off-line and him still very interested in whatever answer you may have. I am available till midnight tonight and a good portion of tomorrow.
The daughter that I have not meet is over forty years old, and has a family of her own...He is a widow of six years...the last two of his marriage was not great...He is so attentive to me, and can hardly stand to be away from for any lenght of time, of which I love....now, can you tell me if he will ask me....I think that the only thing that is holding him up, is that he does not want this daughter to feel like she was left out, because she lives so far away....hoping to hear from you again...thanks
thank you for your additional information and I see no reason why he will not propose to you. You are correct in that you need his daughter's approval for him to proceed. Which means it is important to begin a relationship with her even if it's superficial. His daughter needs to know that you will take good care of her father. All this will come in due time although your preparation for its insureds more chances of success.