Tbf I know he said one lived abroad and the other wasn't local (both been shown in various series - the other one was around series 2 I think? When chummy has her baby)The thing that annoys me now about CTM is that previous storylines are never mentioned again.
In a much earlier series Fred had an adult daughter who wasn’t happy when he married Violet.
Why wasn’t she shown visiting her critically ill father? She wasn’t even mentioned. Poor writing.