Lilly's birth information is available in the "New York Births and Christenings, 1640-1962", database, FamilySearch (https://familysearch.org/ark:/61903/1:1:HQYK-MMT2 : 21 January 2020), Hermann G. Klotz in entry for Lilly Emilie Klotz, .
Lilly and Leonard were married on 7 November 1900 in Manhattan, New York County, New York. Leonard was 28 years old [born ca. 1872) in New York City, New York; Lilly was 22 years old [born ca. 1878] in New York City. See "New York, New York City Marriage Records, 1829-1940," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:24S6-D5B : 10 February 2018), Hermann Gustav Klotz in entry for Leonard Breitwieser and Lillie Klotz, 07 Nov 1900; citing Marriage, Manhattan, New York, New York, United States, New York City Municipal Archives, New York; FHL microfilm 1,570,440.