Thank you all for your replies!
William features twice in the 1861 census. He is also a lodger staying with his Aunt Paterson’s. He is listed as William Bain and Rachel McLain and Robert are there also. Newlands, Peebles.
On Williams birth certificate it has just Esther and states his is illegitimate. On his death certificate he puts Esther McLean & James McLean - obviously fictitious to save embarrassment.
I’m not sure where in Ireland Esther was born, the only knowledge I have of her parents come from her brother Alexander McLeans birth certificate. He was born in 1855 in Peebles.
JohnMcLean abt 1809 • Donoughmore, County Down who married Rachel McCormick abt 1811 • Lisadian Townland, Loughgilly Parish, County Armagh.
As I understand it, although it’s two different counties, they are both close to each other as the crow flys.
William is my GGGrandfather.