FREDERICK (FRED) ROBICHAUD (b. ca. 1855 (1847 in 1901, MAY1846 in 1911), possibly the Fred Robichaud who d. Northumberland Co., NB 8SEP1920,, m.1st ELIZABETH (ELIZA) GALLANT (b. ca. 1861, d. ca. 1898); m. 2nd Northumberland Co., NB 14AUG1899 Catherine/Katherine (Kate) Mahew/Mahen/Mailloux/Mailloux (b. 17MAR1876 (AUG1872 in 1911).)
Robichaud is subject to a variety of spellings, including Robicheau, Robichaux, Robichau, Robicheaud, Robichiou, and some really wild ones. I believe Robichaud is the preferred version, but census enumerators are not noted for spelling skills. I will use Robichaud, even where records give 'Robicheau'.
Birth records gives some children: Josephine, Joseph Alexander and Patrick.
I cannot find them in the 1901 census of New Brunswick. Nor in 1911. In 1891, Frederick (36) and Eliza (30) 'Robichau' are in Chatham Parish. Children were Albert (5), John (3), William (2) and James (1 month.) This was 14APR, so James was b. ca. MAR1891. I assume this is the same couple.
The problem is that, in Chatham Parish, in 1901, is a couple, Fred 'Robicheau' (b. 1847), with a wife, Kate (b. 17MAR1876), apparently a 2nd wife as children are Albert (1887), John (1888), William (1890), James (1891), Xavier (1892), Joseph (OCT1900), Minnie (1889), Josephine (1896), Amos (1898) and Danl (1897.) The family is not well recorded. I think that what is happening is that Eliza d. about 1898-9, and Fred married again. Josephine (1896) appears to be Josephine b. 2MAR1897; and Albert, John, William and James appear to be the same in 1891. There are problems, but it seems to make sense to assume, for now, that this is the 1891 family.
Birth records for Bernard (Barney) (30MAY1904), Katherine Rose (28AUG1908), Annabella (23MAR1914), Frederick (1MAR1902), Mary Agnes (20JAN1906) and Mary Susan (24FEB1911) Robichaud suggest that Kate was either Katherine/Catherine Mahew/Mahen or Katherine Maillou. The spelling is often so atrocious, that it could be either or both. Frederick Robichaud m. Northumberland Co., NB 14AUG1899 Catherine Mahew.
Of these Katherine Rose appears to be Rosina (b. SEP1907) in 1911, and Susan is b. FEB1911. This would make Fred's 2nd wife to be Katherine Mailloux/Mailloux.
Other children by the 2nd marriage appear to be 'Emley' (AUG1900), Patrick (MAR1903) and Agnes (FEB1905; Mary Agnes in birth record.) While they appear in the family of Fred and Kate 'Robicheaud' in Chatham Parish in 1911, I do not include them in the list below as you expressed interest in the 1st marriage. There are questions like, "Where was May (b. 1895) in 1901?" Nevertheless, I believe that these are the same family. Next door to Fred and Kate, in 1911, was William (JUN1890) and Mary (JAN1889) 'Robicheaud', apparently Fred's son by his 1st marriage.
The discrepancies and contradictions in these records is more than normal, it is usual. Census enumerators would rather make wild guesses rather than go back again to a household. Also, people flat out lied to them, or made up stuff when they had no answers.
So, I am pretty sure this is the family you are looking for.
1. ALBERT ROBICHAUD b. Loggieville, Northumberland Co., NB 20DEC1888 (ca. 1886.)
When Albert joined the Canadian Expeditionary Force in World War I, the recruiter spelled the name, 'Robechand', but Albert corrected him. Albert actually signs his name 'albert robichaud'. He was a sawman (logging, lumber), he was unmarried, and gave his next-of-kin as his father, Fred 'Robechand' (as the recruiter wrote it.) He was 5 feet, 5 inches, with dark complexion, hazel eyes and black hair, had tattoos on both arms and was Roman Catholic.
2. JOHN ROBICHAUD b. Loggieville, Northumberland Co., NB 10FEB1887 (ca. 1888.)
John also joined the CEF in WWI. He was a labourer, gave his father as Fred Robichaud of Chatham, was married, 5 feet, 6½ inches, with medium complexion, brown eyes, black hair and a 'K' shaped scar by his left eye. He was roman Catholic.
John 'Robicheaud' (MAY1887) has a wife, Minnie (NOV1885) in Newcastle Parish, Northumberland Co., NB in 1911.
3. WILLIAM ROBICHAUD b. ca. 1889.
Possibly the William Robichaud b. Chatham, NB 1JAN1890, with a wife, Mary (possibly Mary Helen Godin) b. JAN1889; m. 28DEC1909), a millman with defective eyesight. He was 5 feet, 6½ inches with medium complexion, grey eyes, brown hair and Roman Catholic. He was considered fit with restrictions. Part of his attestation form. when he volunteered for the CEF in WWI, suggests he had spent time in the Halifax, NS are.
4. MINNIE ROBICHAUD b. 1889 (maybe John's wife?)
5. JAMES ROBICHAUD b. Chatham, Northumberland Co., NB ca. MAR1891. He only gave his year-of-birth, 1891, and a note states he was medically unfit; so it is not clear whether he was taken in. He was unmarried, a labourer, 5 feet, 5½ inches, dark complexion, brown eyes and black hair, and was Roman Catholic.
He appears to have tried again, as another form has James, 'brother' of Fred Robichaud, b. Chatham 10NOV1891, labourer, 5 feet, 6 inches, dark complexion, blue eyes and black hair, Roman Catholic; joining in Winnipeg a few months later. That he was Fred's brother seems questionable, as does the date-of-birth, as i suspect he was being misleading. He passed the fitness. I may be wrong about these being the same person, but I am very suspicious.
James also joined the CEF, and gave his father as Fred Robichaud of Chatham.
6. PATRICK (XAVIER) ROBICHAUD b. Chatham, Chatham Parish, Northumberland Co., NB 29SEP1892
7. DANIEL (DAN, 'DANL') ROBICHAUD b. MAR1894 (in 1911, 1897 in 1901)
8. MAY ROBICHAUD b. MAY1895 (???)
9. JOSEPH ALEXANDER ROBICHAUD b. Chatham, Chatham Parish, Northumberland Co., NB 20MAY1895 (Alexander b. JAN1896 in 1911)
K. JOSEPHINE ROBICHAUD b. Chatham, Chatham Parish, Northumberland Co., NB 2MAR1897 (1896 in 1911; 1MAR1897 in a second birth record)
L. ALMA (AMOS, but daughter in 1901) ROBICHAUD b. Chatham Parish, Northumberland Co., NB 25OCT1898 (1898 in 1901)