Abraham gave all he had to Isaac. (Bereshit / Genesis 25:5; ESV)
When God called Abraham in his old age to get up and go to an unknown land, God promised to make him into a great nation that would be a blessing to the other nations of the world. It would be another 25 years before God would give him and his wife Sarah, a miracle baby named Isaac. Sarah's inability to have children provides much of the dramatic backdrop to their journey of faith. Prior to Isaac's birth, they devised a scheme whereby Abraham could have a child through one of their servants, but God rejected that so-called solution. The child of promise had to come through Sarah, which he did.
After Sarah's death, Abraham lived for many more years. He married again and had several children through his second wife. Reading through quickly one might jump to the conclusion that this was the fulfillment of God's promise. After trusting God for the miracle baby, notwithstanding their scheme which produced Ishmael, now God was ready to bless Abraham through the natural and legitimate means of a second wife.
God certainly blessed Abraham with these additional children. But even so, Abraham didn't forget God's plans and purposes for Isaac. For though he was generous to all his offspring (25:6), his estate and all it represented was given to Isaac just as God intended.
We don't read of too much drama in Abraham's life between the time of his willingness to offer Isaac to God and the end of his life. During that period, the Torah records his negotiation with the people of the land for a burial plot for Sarah and his sending his servant back to his homeland to find a wife for Isaac. His story ends with his marrying his second wife and the names of his children through her, along with the distribution of his wealth. In all this time we don't read of God speaking to him or leading him in any unusual way. He just lived his life. But in all that time he never forgot his responsibility in ensuring that Isaac and Isaac alone was the recipient of God's promise.
I wonder how many people who had at one time in the midst of dramatic circumstances received special promises or directives from God, but have begun to lose sight of them once the drama subsided. Back then his word to you was so clear, his promises so sure. But now that the drama is history and life has become routine that which you thought you would never forget has all but faded away. But God has not forgotten. Whatever God promised to do in and through your life, no matter how normal your life has become, is still in his heart for you to fulfill. It might take a bit of work to allow God's word to you to be restored to its proper place in your heart, but it's worth it.