Tara Montgomery told ABC News the adoption took place on December 20 in Phoenix, Arizona, after Michael was living with her family for more than a year.
"We got him on February 14, Valentine's Day and now this for Christmas, it's meant to be", says Tara Montgomery, Michael's adoptive mother.
Her daughters have the last name Brown and, as many on social media have pointed out, Michael even looks a lot like his adoptive sisters.
His new family noted that Michael came to them in 2015 as a shy boy, but became more outgoing and confident as time went on.
But when plans to reunite Michael with his biological mother fell through, Montgomery said she felt his adoption was "meant to be".
Michael was set to be adopted last month, but the date was postponed to this week due to the high number of adoptions. She already had other children.
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In those games the Rams beat New Mexico and San Diego State while scoring a combined 112 points and holding each opponent to 31. With a long list of key players returning, including Stevens, the squad should be a contender in the Mountain West next season.
She told the station that Michael is "just what (her) family needed". "He just knew he was being adopted".
"After his mom's rights were severed, I knew he was going to be ours forever", she said. He'd been in foster care for 832 days.
Outside, he posed for photos with his sisters Dezhianna and Jordae. His new mom, Tara Montgomery, shared their heartwarming story.
Montgomery said her daughters have been a tremendous part of the process.
We are so happy that Michael is officially a member of the Brown family, just in time for the holidays. "He is the most loving, smart, amusing and happy kiddo".