Have you checked the parish records? I found the children were baptized at Our Lady of the Valley -- the parish records may provide more information about Catherine (including a marriage date):
Name: Winifred Swan Gender: Female Christening Date: 03 Jul 1898 Christening Place: Our Lady of the Valley, Orange, Essex, New Jersey Birth Date: 14 Apr 1898 Birthplace: Our Lady Of The Valley, Orange, Essex, New Jersey Death Date: Name Note: Race: Father's Name: Thomas Swan Father's Birthplace: Father's Age: Mother's Name: Catherine Dolan
The 1920 census indicates that perhaps Catherine is older than you think:
South Orange, Essex Co., New Jersey
Swan, Thomas, aged 59, married, immigrated 1879, naturalized 1894, born Norway, parents b. same Swan, Catherine, wife, aged 65, married, immigrated 1869, naturalized 1869 Swan, Augustus, son, aged 24, single, born New Jersey
Catherine is deceased by the time of the 1930 census as Thomas is a widower, living with daughter, Katrina Hunt. Have you found her death certificate?