I too had help when I bought my first house. As I grew older, I’ve learned to take the breaks that life hands you but not to live with the hope of a future event happening your way. You have to make it happen yourself.
You seem to have very Asian, or traditional European (Italian) outlook on life.
I would never expect my child to live with me when he grows up. He’ll have a life of his own. If life events bring parents and children back under the same roof, then fine. But expecting your child to live with and care for you in your old age is a lot of pressure for both parent and child.