So the kids and mother figure out the orphan child is trying to ruin the family, she tries to kill the son so they're all in the hospital. Then in the hospital she tries to kill the son again but fails, only the mother and daughter know (the daughter is young and deaf though) the mother slaps the orphan child so the dad is really angry, the hospital sedate the mother and keep her in because they think she's gone back to drinking and now she's beating her orphan child. The dad takes the orphan child and his daughter home.
The daughter goes to sleep and the orphan child puts on a dress and loads of make-up and tries to seduce the dad!!! At the same time some people the mother had been calling to investigate, ring the mother and tell her the orphan child is actually a 33 year old crazy dwarf lady, so the mother gets out of hospital and rushes home. By the time she gets there the orphan dwarf has stabbed the dad to death for refusing her advances. There's a bit of hide and seek in the house, the mother gets her daughter and thinks she's killed the orphan dwarf. So they're outside waiting for police, then the orphan dwarf pops up, they fight, a knife is involved. The mother and orphan dwarf fall in a frozen lake, they scuffle, the mother kicks the orphan dwarf in the face so she dies. The mother and daughter survive.