Hello Rob,
Yes, you are right. Do follow the steps below.
1) Please login to your Themearile account. Then download the “ArileWP Pro Child Theme” package from there.
2) Now copy the comments.php file from the “ArileWP Pro” theme Package and paste the comments.php file in the “ArileWP Pro Child Theme” package.
3) Now upload the zip package of the “ArileWP Pro Child Theme” and activate it.
4) But remember, before upload the zip package of the “ArileWP Pro Child Theme” you need to open this comments.php file and find the “Leave a Reply” heading then change according to you.
Please follow this process carefully and hope it will work for you.
Thanks.