Tony and Oneleigh

This is the relationship by Iron Man, Anthony Stark, and Iron Cross, Oneleigh Stark. Oneleigh is Stark's first born child, his daughter. Her mother was a former fling of Stark's, Carly Bergland.

The two went from having almost no contact during the first 5 years of her life to Stark co-parenting actively with her mother. The two become very close, particularly after Stark becomes a single parent to her following her mother's death in the Decimation.

The two also have a mentor/ protege relationship on top of being father and daughter, with Oneleigh stating that her dad taught her almost everything that she knows.

Their relationship ended when Iron Man died with his wife, best friend, protege, and Oneleigh by his side after sacrificing himself to use the stones to eliminate Thanos and his forces.