Pun of the weak #22

A mom was concerned about her kindergarten son walking to school. He didn't want his mother to walk with him. She wanted to give him the feeling that he had some independence but yet know that he was safe. So she had an idea of how to handle it. She asked a neighbor if she would please follow him to school in the mornings, staying at a distance, so he probably wouldn't notice her. She said that since she was up early with her toddler anyway, it would be a good way for them to get some exercise as well, so she agreed.
The next school day, the neighbour and her little girl set out following behind Timmy as he walked to school with another neighbour boy he knew. She did this for the whole week. As the boys walked and chatted, kicking stones and twigs, Timmy's little friend noticed the same lady was following them as she seemed to do every day all week. Finally he said to Timmy, "Have you noticed that lady following us to school all week? Do you know her?"
Timmy nonchalantly replied, "Yeah, I know who she is."
The friend said, "Well, who is she?"
"That's just Shirley Goodnest," Timmy replied, "and her daughter Marcie. Every night my Mom makes me say the 23rd Psalm with my prayers, and as it says, 'Shirley Goodnest and Marcie shall follow me all the days of my life', I guess I'll just have to get used to it!"