Hi!
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Based on you informaition ******@hotmail.com(daughter) and ******@outlook.com are two completely separate email addresses.
For ease, ******@hotmail.com is yours, and ******@outlook.com could be someone else's email. Your existing Hotmail accounts remain unchanged, and Microsoft has not automatically reserved an Outlook account with the same name.
Thus, it is possible that other people could create those Outlook email addresses. Someone else could have signed up ******@outlook.com at a later part during the transition.