They were seen on surveillance cam following her in black SUV I believe. Just long enough to see which house she went into.
She was walking home with the baby, after getting off the bus. It is quite normal for someone to stop and say OH WHAT A SWEET BABY when walking around town. I have done that myself. Maybe she was standing on the corner waiting for the light, or something like that, and the strangers said something and she replied. That is normal everyday interactions, imo.
Police released the video showing SUV following the bus. Sounds like this woman saw mother and the baby getting on the bus, then followed the bus. Then followed her after she got of the bus to see where she lives?
I don't think mother saw the man at that time. Also, she probably didn't realize that the woman was following her.
I think it's rather obvious suspects didn't know the mother. If the knew her, there would be no need to follow her, because they would have already known where she lives.