Rufus had managed to find out approximately where Beth lived with her parents. He didn't need to know her exact address. He found a park nearby and waited. Nothing. There were mothers pushing babies, but not Beth. Maybe tomorrow.
That evening he constructed his plans, with inspiration provided by Mac2.
The next day he was rewarded. Arriving around 10am he sat on a park bench. Mothers passed and after a while he saw what he thought was Beth, pushing a pram. He followed her discreetly until she sat on a bench to read her book. Baby was asleep.