Correct child_frame_id for Odometry

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I have a physical, two wheel drive differential robot which has the following links setup in a URDF file:

base_footprint -> base_link -> then several other links attached to base_link (e.g. right_wheel, left_wheel, lidar_link, imu and camera_link)

I'm using ROS2 Galactic and I can visualize the robot just fine in Rviz2.

I wrote my own differential drive node that reads encoded "ticks" from the wheels and publishes three messages: nav_msgs::msg::Odometry
geometry_msgs::msg::TransformStamped sensor_msgs::msg::JointState

The nav and geometry messages are currently setting the child frame to "base_link". Is this correct? Or should it be "base_footprint" since that is the root of my robot's frames.