Laravel Validation Rule - At least one input value change must be made

I have a model with title, subtitle, date and am building a form that will allow a user to submit a change request.

How can I validate to ensure at least one edit is made comparing the input fields to database values?

I think the below would ensure the title entered is different from the value in 'different:', but how would I only do this for at least one field?

public function rules()
{

    return [
        'title' => [
            'required',
            'different:Dynamic Title name here',
            'string',
            'max:60',
            'not_regex:/[\x{1F600}-\x{1F64F}]/u'
        ],
        'subtitle' => [
            'string',
            'nullable',
            'max:90',
            'not_regex:/[\x{1F600}-\x{1F64F}]/u'
        ]

    ];

}

e.g. Title, Subtitle, Date fields are shown. A user must edit at least one of them from the current set database values in order to submit.

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