You won't really know 100% unless she's tested.
If one of her parents had the gene mutation for
Lynch Syndrome, she has a 50-50 chance to inherit the gene mutation, which puts her at a higher risk for certain cancers.
She can get a genetic evaluation to determine this.
Search under "Lynch Syndrome Testing Algorithm"
if interested- very technical though!
If the results come back negative, that means that you are likely in the clear as well, since chances of your father having this gene mutation, would be very slim!
Note that young age is not one of the criteria.
It is just that historically Lynch Syndrome causes cancer in people at a younger age compared to the general population.
I hope this helps,
Niko