I believe this is Helena Bonham Carter and her actual child, not something from a movie. But also, this (to me) is what Andromeda Tonks and Teddy would look like, a few years after the Battle of Hogwarts. Except Teddy's hair would be bubblegum pink.
Bellatrix Lestrange (née Black) – 2 May, was a pure-blood witch, the eldest daughter.
Sweeney Todd Movie - Helena Bonham Carter - Costume designed by Colleen Atwood