Returning multiple lists from one SQLAlchemy query organized by a dict attribute FLASK

Question

I am trying to write a python function that receives a list of all VolunteerReports from a DB and then organizes them into separate lists based on their "report_category", and returns one dict with many lists inside.

my current function:

def get_volunteer_reports_for_client(volunteer_id, client_id):
    reports_obj = {}

    volunteer_reports = db_session.query(VolunteerReport).filter(
        VolunteerReport.volunteer_id == volunteer_id, \
            VolunteerReport.client_id == client_id).all()

    if not volunteer_reports:
        return []

    res = [volunteer_report_schema.dump(volunteer_report) for volunteer_report in volunteer_reports]

    for r in res:
        reports_obj[r['report_category']] = [r]

    return reports_obj

res returns a list that looks like so:

[
    {
        "client_id": 24,
        "created_at": "2022-02-10 16:41:52.538363",
        "id": 1,
        "report": "This is the first report",
        "report_category": "Client Assigned",
        "volunteer_id": 23
    },
    {
        "client_id": 24,
        "created_at": "2022-02-10 16:41:52.623236",
        "id": 2,
        "report": "This is the SECOND report",
        "report_category": "Client Assigned",
        "volunteer_id": 23
    },
    {
        "client_id": 24,
        "created_at": "2022-02-10 16:41:59.493851",
        "id": 3,
        "report": "This is the THIRD report",
        "report_category": "Fulfilled The Need",
        "volunteer_id": 23
    },
    {
        "client_id": 24,
        "created_at": "2022-02-10 16:43:06.364411",
        "id": 4,
        "report": "This is the FOURTH report",
        "report_category": "Fulfilled The Need",
        "volunteer_id": 23
    }
]

reports_obj currents returns this:

{
    "Client Assigned": [
        {
            "client_id": 24,
            "created_at": "2022-02-10 16:41:52.623236",
            "id": 2,
            "report": "This is the SECOND report",
            "report_category": "Client Assigned",
            "volunteer_id": 23
        }
    ],
    "Fulfilled The Need": [
        {
            "client_id": 24,
            "created_at": "2022-02-10 16:43:06.364411",
            "id": 4,
            "report": "This is the FOURTH report",
            "report_category": "Fulfilled The Need",
            "volunteer_id": 23
        }
    ]
}

At this point, it is omitting some of the entries and only returning the last indexed entry with that "report_category". Any advice?