"Go Hart go!" Meghan cheered as the boy attempted to climb a play cushion.
"Go Hart go!" Aspen echoed repeatedly.
Meghan has documented Hart's health battle on Instagram, with photos and videos of his doctor visits and therapies.
On Friday, she posted a photo of her holding Hart while standing in a hyperbaric compressed oxygen chamber.
"Four times a week either Jimmy or I 'dive' with Hart in a hyperbaric compressed oxygen chamber (HBOT)," she wrote. "After 5 dives we are already seeing progress: lifting his left leg on stairs when his right is restrained, bear crawling (perhaps trying to stand?), more willingly taking steps with assistance, and cruising from the couch to the coffee table. Is it because of this alternative therapy, is it because he's just getting older, is it because of PT, or is it because of his 3x/weekly chiropractor visits? Who knows, but it's not hurting! Go Hart, go! #GoHartGo #pediatricHBOT #whateverittakes."