Complex sentence: When removing their comment, you have to remove the replies to their comments as well, or it will be confusing, this is why you need to be careful when doing this, since you are removing other person's comments.
Split into simpler sentences: When removing their comment, you have to remove the replies to their comments as well, or it will be confusing. This is why you need to be careful when doing this, since you are removing other person's comments.