I would ask your vet, but it does seem that maybe she's just going through an adjustment period. You do great to take her on 4 mile walks/run every day - that's awesome; she is a lucky dog. Maybe with your son now walking himself, she's feeling like he's getting all the attention. . . . ?? If she's had a recent check up and nothing is medically wrong, it may just be an adjustment period. She is "growing up" herself now at. Is she fixed? Maybe her own changes, coupled with the baby's changes, are regressing her a bit. It seems odd that she hides one day and the next she's craving attention . . . ? Sorry I don't really have an answer, but as an animal lover, I pray everything is ok.