“The young couple has a successful cleaning business...”
Dry cleaning or house cleaning business... irregardless of which, maybe they saw something they should not have seen. Hopefully, they are protected and in a secret witness program rather than being taken out.
Or they were involved in something illegal(drugs). Let's not forget the Powell case either. The guy could have killed his wife and is on the run with the baby.
In many of these cases one person in the family is up to no good.