Relationships adding child posts to parent in the front end

Hi,

Thank you for reaching out.

You can use the extension MB Frontend Submission to create a post on the frontend and create connections to other posts also.

Each relationship meta box has an ID: {$relationship_id}_relationships_from and {$relationship_id}_relationships_to. You can include these IDs in the form shortcode to show it on the front end.

Get more details on the documentation https://docs.metabox.io/extensions/mb-frontend-submission/, and refer to this topic https://support.metabox.io/topic/mb-relationships-mb-frontend-submission/.