A woman whose mother was murdered when she was a child of twelve, is now, fifteen years later, working as a detective and still pursuing her mother's killer, who, it turns out, is closer than she thinks.
The second line in the logline (“…was a child of twelve, is now, fifteen years later, …”) is a very long way of saying 27yo. No need for this line as the MC’s age has no baring on the plot.
These kind of sentences “… is closer than she thinks…” work against a logline as they are vague and lack detail. Closer in what way? Physically? Emotionally? Geographically? If the murderer is a friend, family member or work colleague then say so in the logline.
The logline as a whole doesn’t describe a plot it describes a situation; this woman is doing this thing. What a logline nbeeds to do is describe a series of events that are connected via a cause and eefect relationship; because of this thing this woman must achieve this goal.
What is the MC’s goal? What is the inciting incident? The logline should be able to answer these questions.
Hope this helps.