Before Maria Theresa was born, the Emperor Charles VI and his wife Elisabeth had a boy, Leopold Johann, who lived for almost six months, but died as infant. Six months after his death, Maria Theresa was born, and due to the Pragmatic Sanction she became the heir of the Habsburg territories.
But WI Leopold Johann had survived, making the succession continue through a male line? Maria Theresa birth isn't affected, but would she still be married to the Duke of Lorraine? Also, it would mean no War of Austrian Succession, and Prussia would have no reason to invade Silesia (at least not immediately). Would Austria still continue opposed to France ITTL?
But WI Leopold Johann had survived, making the succession continue through a male line? Maria Theresa birth isn't affected, but would she still be married to the Duke of Lorraine? Also, it would mean no War of Austrian Succession, and Prussia would have no reason to invade Silesia (at least not immediately). Would Austria still continue opposed to France ITTL?