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1. It's not bad to have pages that are not directly linked to your site. In fact a good lot of PPC landing pages aren't typically linked from anywhere within the navigation or website itself. Keep the page in the sitemap if you want it to remain indexed but if you only care about the direct traffic, it doesn't need to stay. You can definitely 301 the old page to the new one but you said you previously hid the parent? I would only 301 redirect if you're 100% sure this is the way it will stay forevermore. So it really depends on why you're removing and what you essentially want to happen.