Did Guru Nanak have siblings

Answer 1

YES,

In- fact Guru Nanak had one sister Bibi Nanaki. Guru Nanak did not have any brothers.

Bibi Nanaki was five years older than Guru Nanak; she was the first to recognize his spiritual eminence and to become his devotee. She is often credited as becoming the first Sikh. She protected Nanak from their father's wrath, when repeatedly he disappointed and angered him. She was with him throughout the early years of his childhood.

Answer 2

Mata Sulakni was Guru Nanak's wife