Caleb Flynn's Young Daughters Rip Into Him In Statement Read at Sentencing

Caleb Flynn was sentenced to life in prison for murdering his wife, Ashley, but the biggest blow might've come from his young daughters.

The girls’ uncle, Matthew Keyt, read 10-year-old Ava's scathing statement in court before the "American Idol" alum's sentencing.

She wrote ... "Dear Daddy, I don't even know where to start. How could you do such a thing?"

Ava's letter went on to say ... "Mommy was the perfect person, the absolute perfect person. What did she ever do to make you hate her so much?"

She later added ... "She was my best friend and then you chose to kill the only mother I ever had."

Ava also tore into his affair with Alleigha Botner, saying Flynn and Botner "sinned big time" ... "How could you cheat on her and go to that awful girl Alleigha? I never liked her."

Flynn's mother-in-law, Jill Smith, then read 12-year-old Alyssa's statement ... where she goes scorched earth on her dad.

She doesn't address him as "Daddy," like Ava did -- she just calls him Caleb -- and writes ... "I loved you deeply with all my heart, and it's sad that you can't love anyone but yourself."

Alyssa's letter continued ... "You have already caused so much pain to your family and the world. The least you could do is tell everyone that you did it and receive your outcome."

She ripped into him, adding ... "Did you really even think about how much pain you would bring your own two daughters? By the way, Ashley Flynn was the best thing that ever happened to you."

Alyssa went on to say Flynn made her feel like "an idiot" for thinking she could trust him, before delivering the fatal blow ... "And by the way, I don't plan on coming to see you."

Caleb was convicted and sentenced for Ashley's murder, after prosecutors argued he'd shot her twice in the back of the head and staged the scene to look like a break-in.