Peter Hamling Born: 1835 in Prussia
Katherine Marx Born: 1840 in Prussia Died: 9/30/1932 in SD
Children: all born in MN
Amelia or Emma Born: 1863
Katherine Born: 1865 Died 1/19/1947 in SD last name: Kosse
Charles Born: 1868
Mathew Born: 1872
Theresia Born: 1874
Mary Born: 1876
Maggie Born: 1877
Peter J Born: March 25, 1879
There is at least one more girl but 1890 census were distroyed so we can't see if anyone else was born. But according to the 1910 census Peter Jr was living with a sister who was born in 1881. I can't make out the name. Peter SR must have died before 1900 because I can't find him after 1880, only Peter Jr.
1880 Census in Minnesota with Last Name: Helming
Peter Hamling JR:
1900 Census in Grant County SD living with Kosse family
1910 Census in Spokane WA living w/ his sister and her husband George Northway
1920 Census back in Grant County SD with wife Lena or Dena C, Son Gilbert
1930 Census Grant County SD with Lena or Dena C, Gilbert, Elisa, Ivan, Leo
I don't have anything yet, about Peter Sr. parents.

Hope this helps!