Set of two photographs of children identified on reverse as Helen and Harold; the photographs were taken by the McKay studio of Calais, Maine. One of the photographs is dated Christmas, 1889.
Using Census records and the names of the uncles to whom the photographs were inscribed, I'm guessing that the siblings are Helen and Harold Murchie of Calais.
The photograph above was inscribed to Uncle Alex, who might have been Alexander MacTavish, husband of the siblings' paternal aunt, Mary Adeline (Murchie) McTavish.
The photograph below, dated Christmas 1889, was inscribed to Uncle Kemp, assuming I'm deciphering the faint handwriting correctly.
Uncle Kemp was likely David Kemp Harmon of Milltown, St. Stephen, New Brunswick; he was a brother of the siblings' mother Cora Hale (Harmon) Murchie.
Sadly, Helen died of diabetes on 2 July 1901. [Ironically, Dr. Charles Best, co-discoverer of insulin in the 1920s, was born in West Pembroke, Maine, not far from Calais.]
Harold Hale Murchie was born 8 March 1888 at Calais, Maine, son of George Albert Murchie and Cora Hale (Harmon) Murchie. He graduated from Dartmouth College and received a law degree from Harvard University.
He set up a law practice at Calais and later served in both houses of the Maine State Legislature and as Chief Justice of the Supreme Court of Maine.
On 15 October 1913, at Calais, he married Edith Jessie Ross, daughter of Henry Butler Ross and Lelia Miranda (Bridges) Ross. She was born 23 March 1888 at St. Stephen, New Brunswick. Her mother was a native of the aforementioned Pembroke, Maine.