Was the neutered father guinea pig responsible for 2 babies?

Mar 24, 2015

The pair of guinea pigs gave birth to 1 male and 1 female on   before the sire was neutered.

Parents  about 1 year old.
Sep 3, 2014   dam gave birth to a male and a female. F1 generation
Oct 7, 2014   sire was neutered by Dr Daniel
Feb 13, 2015  dam gave birth to 2 males. F2 generation.
Was the neutered sire the father? The Korean lady asked me.  Dr Daniel said that the neutered sire should be separated from the dam for 3 months after neuter.

Guinea pigs mature at 3 months of age.
Gestation period 59 - 73 days or 2 months.





Dec 3, 2014  F1 male will mature from 3 months and will mate with the mother.
Feb 13, 2015 (2 months' gestation, mating on Dec 13, 2014 by F1 son).
So the neutered father was NOT responsible.