The court heard Machin had been having problems with Bollen, who lived two doors away, for several months before the fatal attack.
She had become annoyed by the constant noise made by her children and the number of times they kicked footballs into her garden.
Miss Machin eventually punctured one of the balls with a knife before throwing it back over the fence on August 23.
Bollen and a group of women charged round to the house and banged on the door shouting: "You might not come out now Kelly, but I'm going to kill ya."
They eventually left but Bollen then returned 20 minutes later with her father.
The pair burst into the house after the door was opened by Miss Machin's friend, and launched the attack.
Bollen punched her in the face several times before Jelly pushed her backwards, fracturing five ribs, which ruptured her chest cavity.
Machin received hospital treatment but she was found dead on her sofa on September 5, less than two weeks after the assault.
Judge Nicholas Dean QC, sentencing, told them: "In my view, the evidence the jury heard demonstrates very clearly that you went together to Kelly Machin's home when both of you were in an irate and volatile state of mind, when you were both intent on a confrontation with her.
"Whether her death was painful we cannot know, but it was certainly lonely."
He added: "They forced their way into Kelly Machin's home - they were violent trespassers.
"Both used unpleasant violence towards her.
"Their violence caused Kelly Machin's death. Neither has shown real remorse.
"In keeping with her character Natalie Bollen reacted hysterically to Miss Machin's behaviour.'
Speaking after the case, Detective Chief Inspector Martin Smalley, of Leicestershire Police, said: "A seemingly minor incident resulted in a person losing their life.
"The defendants' actions on that day were excessive and they attacked Kelly without regard for the consequences.
"They now face a lengthy prison sentence and two families have been left devastated.'
John Cammegh, defending Bollen, said: "It was an impetuous moment of madness on the part of Miss Bollen. She lost her temper. Things had been boiling for a long time - she simply snapped.
"Sadly the consequences were far beyond anything she could have imagined and is something she will be eternally ashamed of and will regret forever.
"She's terribly, terribly sorry to the family of the deceased for what happened.'
William Mousley QC, defending Jelly, said: "It's a very unusual case - as a result of a single angry push - and he's responsible for the wholly unforeseen death of Kelly Machin.
"He initially went there to do the right thing by his vulnerable daughter and then did the wrong thing and lost his control in the way he did."