Shanks never thought he'd be a father, well, not a proper one at least.
He had a natural talent with kids, or some said.
However, being a pirate, especially one with such a high bounty on his head, the thought of having kids didn't ever crossed his mind. It'll be too risky.
He was fine with a lover if he ever got one. But when his little girl was born, Shanks knew she'll have him absolutely wrapped around her tiny, chubby fingers.
Some could say he was enabling his daughter, and to some extent, he was. Whatever his princess wanted, she got. Shanks was, ultimately, his daughter most fierce and loyal supporter, despite of the trouble the little girl got into while growing up because of course, not only was she being raised around pirates but also, because she was still Shanks child and the troublemaker genes seemed to run in their blood.
Nonetheless, Shanks still loved his little princess to bits.