No legitimate ones. That was the whole problem!
Actually, she had many siblings, but they were all bastards. Her brother James and her sister Jean (wife to the Earl of Agyle) are two of them.
Yes, Prince James or James VI. Who became James I of England after the death of Queen Elizabeth I.
yes a dog
Yes she did. She had many grandchildren. Her son James had nine children. The current Queen of England is a direct descentant of Mary, Queen of Scots.
Yes she had three Francis Henry and john
There is no evidence to suggest she wasn't a true queen. She was forced to abdicate in order for her son James VI to take the throne so she wasn't queen after abdication (by definition).