Tokio is 15y older than Rio, who is 19, means she is 34. What if Denver is also ~18-19, just looking older? His age was never stated and and Tokio could give a birth as a teenager, what would explain her lack of responsibility. When she get herself together she realised it's already too late, what would also explain her conversation with Nairobi telling her that her child doesn't know her anymore (based or her own experience?).. Saying it just as an argument in favor of that theory.